Mercruiser 4 Cyl 3.0 Service Manual

Number 26

Printed in U.S.A. 90-861329--1 MARCH 1999 1999, Mercury Marine

MARINE ENGINES

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GM 4 Cylinder 181 cid (3.0L)

MerCruiser # 26 GM 4 Cylinder 181 cid (3.0L) 90-861329--1

MerCruiser # 26 GM 4 Cylinder 181 cid (3.0L) 90-861329--1

90-861329--1 MARCH 1999 Page i

Notice

Throughout this publication, “Dangers”, “Warnings” and “Cautions” (accompanied by the In-ternational HAZARD Symbol ) are used to alert the mechanic to special instructions con-cerning a particular service or operation that may be hazardous if performed incorrectly orcarelessly. OBSERVE THEM CAREFULLY!

These “Safety Alerts” alone cannot eliminate the hazards that they signal. Strict complianceto these special instructions when performing the service, plus “Common Sense” operation,are major accident prevention measures.

DANGERDANGER - Immediate hazards which WILL result in severe personal injury or death.

WARNINGWARNING - Hazards or unsafe practices which COULD result in severe personal in-jury or death.

CAUTIONHazards or unsafe practices which could result in minor personal injury or productor property damage.

Notice to Users of This Manual

This service manual has been written and published by the Service Department of MercuryMarine to aid our dealers’ mechanics and company service personnel when servicing theproducts described herein.

It is assumed that these personnel are familiar with the servicing procedures of these prod-ucts, or like or similar products manufactured and marketed by Mercury Marine, that theyhave been trained in the recommended servicing procedures of these products which in-cludes the use of mechanics’ common hand tools and the special Mercury Marine or recom-mended tools from other suppliers.

We could not possibly know of and advise the service trade of all conceivable proceduresby which a service might be performed and of the possible hazards and/or results of eachmethod. We have not undertaken any such wide evaluation. Therefore, anyone who usesa service procedure and/or tool, which is not recommended by the manufacturer, first mustcompletely satisfy himself that neither his nor the products safety will be endangered by theservice procedure selected.

All information, illustrations and specifications contained in this manual are based on thelatest product information available at the time of publication. As required, revisions to thismanual will be sent to all dealers contracted by us to sell and/or service these products.

It should be kept in mind, while working on the product, that the electrical system and ignitionsystem are capable of violent and damaging short circuits or severe electrical shocks. Whenperforming any work where electrical terminals could possibly be grounded or touched bythe mechanic, the battery cables should be disconnected at the battery.

Any time the intake or exhaust openings are exposed during service they should be coveredto protect against accidental entrance of foreign material which could enter the cylinders andcause extensive internal damage when the engine is started.

Page ii 90-861329--1 MARCH 1999

It is important to note, during any maintenance procedure replacement fasteners must havethe same measurements and strength as those removed. Numbers on the heads of the met-ric bolts and on the surfaces of metric nuts indicate their strength. American bolts use radiallines for this purpose, while most American nuts do not have strength markings. Mis-matched or incorrect fasteners can result in damage or malfunction, or possibly personalinjury. Therefore, fasteners removed should be saved for reuse in the same locations when-ever possible. Where the fasteners are not satisfactory for re-use, care should be taken toselect a replacement that matches the original.

We reserve the right to make changes to this manual without prior notification.

Refer to dealer service bulletins for other pertinent information concerning the products de-scribed in this manual.

Engine Mechanical Components

Many of the engine mechanical components are designed for marine applications. Unlikeautomotive engines, marine engines are subjected to extended periods of heavy loadand wide-open-throttle operation and, therefore, require heavy-duty components. Specialmarine engine parts have design and manufacturing specifications which are required toprovide long life and dependable performance. Marine engine parts also must be able toresist the corrosive action of salt or brackish water that will rust or corrode standard automo-tive parts within a short period of time.

Failure to use recommended Quicksilver service replacement parts can result in poor en-gine performance and/or durability, rapid corrosion of parts subjected to salt water andpossibly complete failure of the engine.

Use of parts other than recommended service replacement parts, will void the warranty onthose parts which are damaged as a result of the use of other than recommended replace-ment parts.

Replacement Parts

WARNINGElectrical, ignition and fuel system components on MerCruiser Engines and SternDrives are designed and manufactured to comply with U.S. Coast Guard Rulesand Regulations to minimize risks of fire or explosion.

Use of replacement electrical, ignition or fuel system components, which do notcomply to these rules and regulations, could result in a fire or explosion hazard andshould be avoided.

When servicing the electrical, ignition and fuel systems, it is extremely importantthat all components are properly installed and tightened. If not, any electrical or ig-nition component opening would permit sparks to ignite fuel vapors from fuel sys-tem leaks, if they existed.

Models Covered in This ManualModel Serial Number Model Year

MCM 3.0L Alpha OL010042 and Above 1998 -

1

2

3

4

5

6

7

8

Important Information

Removal And Installation

Engine

Electrical System

Fuel System

Cooling System

Exhaust System

Power Steering

90-861329--1 MARCH 1999 Page iii

Service Manual Outline

Section 1 - Important InformationA - General InformationB - MaintenanceC - Troubleshooting

Section 2 - Removal and InstallationA - MCM 3.0L (181 CID) - Alpha Drive

Section 3 - EngineA - 3.0L (181 CID)

Section 4 - Electrical SystemA - Starting SystemB - Ignition SystemC - Charging SystemD - InstrumentationE - Wiring Diagrams

Section 5 - Fuel SystemA - Fuel PumpB - MerCarb 2-Barrel

Section 6 - Cooling SystemA - Seawater Cooled ModelsB - Closed Cooled Models

Section 7 - Exhaust SystemA - Exhaust Manifolds / Elbows

Section 8 - Power SteeringA - Power Steering

Page iv 90-861329--1 MARCH 1999

THIS PAGE IS INTENTIONALLY BLANK

1A

GENERAL INFORMATIONSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 1A-1

IMPORTANT INFORMATIONSection 1A - General Information

Table of Contents

Table of Contents 1A-1. . . . . . . . . . . . . . . . . . . . . Introduction 1A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . How to Use This Manual 1A-2. . . . . . . . . . . . . . .

Page Numbering 1A-2. . . . . . . . . . . . . . . . . . . How to Read a Parts Manual 1A-3. . . . . . . . . . . Directional References 1A-4. . . . . . . . . . . . . . . . . Engine Rotation 1A-4. . . . . . . . . . . . . . . . . . . . . . . Engine Serial Number Locations 1A-5. . . . . . . .

Propeller Information 1A-5. . . . . . . . . . . . . . . . . . Water Testing New Engines 1A-6. . . . . . . . . . . . Boat and Engine Performance 1A-6. . . . . . . . . .

Boat Bottom 1A-6. . . . . . . . . . . . . . . . . . . . . . . Marine Fouling 1A-8. . . . . . . . . . . . . . . . . . . . . Weight Distribution 1A-9. . . . . . . . . . . . . . . . . . Water in Boat 1A-9. . . . . . . . . . . . . . . . . . . . . . Elevation and Climate 1A-9. . . . . . . . . . . . . . .

GENERAL INFORMATION SERVICE MANUAL NUMBER 26

Page 1A-2 90-861329--1 MARCH 1999

Introduction

This comprehensive overhaul and repair manual is designed as a service guide for the mod-els previously listed. It provides specific information, including procedures for disassembly,inspection, assembly and adjustment to enable dealers and service mechanics to repair andtune these engines.

Before attempting repairs or tune-up, it is suggested that the procedure first be read throughto gain knowledge of the methods and tools used and the cautions and warnings requiredfor safety.

How to Use This Manual

This manual is divided into sections which represent major components and systems.

Some sections are further divided into parts which more fully describe the component.

Sections and section parts are listed on the “Service Manual Outline” page following “V-8Models Covered in This Manual” page.

Page NumberingTwo number groups appear at the bottom of each page. Following is an example anddescription.

a b c d e f g

a - Section Numberb - Section Partc - Page Numberd - Manual Part Numbere - Revision Numberf - Month Printedg - Year Printed


90-861329--1 MARCH 1999 Page 1A-3

How to Read a Parts Manual

POWER STEERING PUMP ASSEMBLY

1

2

3 4

5

6

7

8

9

10

REF.NO. PART NO. SYM. QTY. DESCRIPTION

1 90507A12 1 PUMP ASSEMBLY–Power Steering2 36- 95805 1 CAP3 73873A1 1 PULLEY4 16- 41877 1 STUD5 57- 65607T 1 V-BELT6 32- 806684 1 HOSE–Pressure (FITTINGS ON BOTH ENDS)7 25- 89879 1 O-RING8 25- 806232 1 O-RING9 13- 35048 1 LOCKWASHER (3/8 in.)10 61990 1 CABLE TIE

REF. NO. : Number shown next to part on exploded view

PART NO. : Mercury Part Number for ordering. If NSS (not sold separately) sometimes GMpart number will be given in description column.

QTY. : The quantity that must be ordered.

DESCRIPTION : Description of part, what parts are included with a part (all indented itemscome with the main item above the indented parts), serial number information, and specialinformation.


Page 1A-4 90-861329--1 MARCH 1999

Directional References

Front of boat is bow; rear is stern. Starboard side is right side; port side is left side. In thismaintenance manual, all directional references are given as they appear when viewing boatfrom stern looking toward bow.

72000

STARBOARD(RIGHT)

PORT(LEFT)

FORE or BOW(FRONT)

AFT or STERN(REAR)

Engine Rotation

Engine rotation is determined by observing flywheel rotation from the rear (stern end) of theengine looking forward (toward water pump end). Propeller rotation is not necessarily thesame as engine rotation. When ordering replacement engine, short blocks or parts forengine, be certain to check engine rotation. Do not rely on propeller rotation in determiningengine rotation.

72001

Standard Left Hand Rotation


90-861329--1 MARCH 1999 Page 1A-5

Engine Serial Number Locations

71559

a

b

a - Serial Number Plateb - Starter Motor

Propeller Information

Refer to the “Propeller” section in appropriate MerCruiser Sterndrive Service Manual, ororder publication 90-86144, “What You Should Know About Quicksilver Propellers.”

Changing diameter, pitch or coupling of a propeller will affect engine rpm and boat perfor-mance. The blade configuration also will affect performance. Two like propellers, same pitchand diameter, from two different manufacturers also will perform differently.

It is the responsibility of the boat manufacturer and/or selling dealer to equip the boat withthe correct propeller to allow the engine to operate within its specified rpm range atwide-open-throttle (W.O.T.).

Because of the many variables of boat design and operation, only testing will determine thebest propeller for the particular application.

To test for correct propeller, operate boat (with an average load onboard) at W.O.T. andcheck rpm with an accurate tachometer. Engine rpm should be near top of the specifiedrange so that, under heavy load, engine speed will not fall below specifications.

If engine exceeds the specified rpm, an increase in pitch and/or diameter is required.

If engine is below rated rpm, a decrease in pitch and/or diameter is required.

Normally, a change of approximately 400 rpm will be achieved for each single pitch changeof a propeller.

CAUTIONIf a propeller is installed that does not allow engine rpm to reach the specifiedfull-throttle rpm range, the engine will “labor” and will not produce full power.Operation under this condition will cause excessive fuel consumption, engineoverheating and possible piston damage (due to detonation). On the other hand,installation of a propeller that allows engine to run above the specified rpm limit willcause excessive wear on internal engine parts which will lead to premature enginefailure.


Page 1A-6 90-861329--1 MARCH 1999

Water Testing New Engines

Use care during the first 20 hours of operation on new MerCruiser engines or possibleengine failure may occur. If a new engine has to be water-tested at full throttle before thebreak-in period is complete, follow this procedure.

1. Start engine and run at idle rpm until normal operating temperature is reached.

2. Run boat up on plane.

3. Advance engine rpm (in 200 rpm increments) until engine reaches its maximum ratedrpm.

IMPORTANT: Do not run at maximum rpm for more than 2 minutes.

Boat and Engine Performance

Boat BottomFor maximum speed, a boat bottom should be as flat as possible in a fore-aft direction(longitudinally) for approximately the last 5 ft (1.5 m).

72002

a

a - Critical Bottom Area


90-861329--1 MARCH 1999 Page 1A-7

For best speed and minimum spray, the corner between the bottom and the transom shouldbe sharp.

72003a

bc

a - Bottomb - Cornerc - Transom

The bottom is referred to as having a “hook” if it is concave in the fore-and-aft direction. Ahook causes more lift on the bottom near the transom and forces the bow to drop. Thisincreases wetted surface and reduces boat speed. A hook, however, aids in planing andreduces any porpoising (rhythmical bouncing) tendency. A slight hook is often built in by themanufacturer. A hook also can be caused by incorrect trailering or storing the boat withsupport directly under the transom.

72004a

a - Hook

A “rocker” is the reverse of a hook. The bottom is convex or bulged in the fore-and-aft direc-tion. It can cause the boat to porpoise.

72005a

a - Rocker

Any hook, rocker or surface roughness on the bottom, particularly in the all-importantcenter-aft portion will have a negative effect on speed, often several miles per hour on a fastboat.


Page 1A-8 90-861329--1 MARCH 1999

Marine FoulingFouling is an unwanted build-up (usually animal-vegetable-derived) occurring on the boat’sbottom and drive unit. Fouling adds up to drag, which reduces boat performance. In freshwater, fouling results from dirt, vegetable matter, algae or slime, chemicals, minerals andother pollutants. In salt water, barnacles, moss and other marine growth often producedramatic build-up of material quickly. Therefore, it is important to keep the hull as clean aspossible in all water conditions to maximize boat performance.

Antifouling paint, if required, may be applied to boat hull observing the following precautions.

IMPORTANT: DO NOT paint anodes or MerCathode System reference electrode andanode, as this will render them ineffective as galvanic corrosion inhibitors.

CAUTIONAvoid corrosion damage. Do not apply antifouling paint to MerCruiser drive unit ortransom assembly.

IMPORTANT: If antifouling protection is required, Tri-Butyl-Tin-Adipate (TBTA) baseantifouling paints are recommended on MerCruiser boating applications. In areaswhere Tri-Butyl-Tin-Adipate base paints are prohibited by law, copper base paintscan be used on boat hull and boat transom. Corrosion damage that results from theimproper application of antifouling paint will not be covered by the limited warranty.Observe the following:

Avoid an electrical interconnection between the MerCruiser Product, Anodic Blocks,or MerCathode System and the paint by allowing a minimum of 1 in. (26mm)UNPAINTED area on transom of the boat around these items.

71176a b

a - Antifouling Paintb - MINIMUM 1 inch (26 mm) Unpainted Area


90-861329--1 MARCH 1999 Page 1A-9

Weight DistributionWeight distribution is extremely important; it affects a boat’s running angle or attitude. Forbest top speed, all movable weight - cargo and passengers - should be as far aft as possibleto allow the bow to come up to a more efficient angle (3 to 5 degrees). On the negative sideof this approach is the problem that, as weight is moved aft, some boats will begin an unac-ceptable porpoise.

Secondly, as weight is moved aft, getting on plane becomes more difficult.

Finally, the ride in choppy water becomes more uncomfortable as the weight goes aft. Withthese factors in mind, each boater should seek out what weight locations best suit his/herneeds.

Weight and passenger loading placed well forward increases the “wetted area” of the boatbottom and, in some cases, virtually destroys the good performance and handling charac-teristics of the boat. Operation in this configuration can produce an extremely wet ride, fromwind-blown spray, and could even be unsafe in certain weather conditions or where bowsteering may occur.

Weight distribution is not confined strictly to fore and aft locations, but also applies to lateralweight distribution. Uneven weight concentration to port or starboard of the longitudinalcenterline can produce a severe listing attitude that can adversely affect the boat’sperformance, handling ability and riding comfort. In extreme rough water conditions, thesafety of the boat and passengers may be in jeopardy.

Water in BoatWhen a boat loses performance, check bilge for water. Water can add considerable weightto the boat, thereby decreasing the performance and handling.

Make certain that all drain passages are open for complete draining.

Elevation and ClimateElevation has a very noticeable effect on the wide-open-throttle power of an engine. Sinceair (containing oxygen) gets thinner as elevation increases, the engine begins to starve forair. Humidity, barometric pressure and temperature do have a noticeable effect on thedensity of air. Heat and humidity thin the air. This phenomenon can become particularlyapparent when an engine is propped out on a cool dry day in spring and later, on a hot, humidday in August, does not have the same performance.

Although some performance can be regained by dropping to a lower pitch propeller, thebasic problem still exists. The propeller is too large in diameter for the reduced power output.A Quicksilver Propeller Repair Station or experienced marine dealer can determine howmuch diameter to remove from a lower-pitch propeller for specific high-elevation locations.In some cases, installing high altitude gears in the drive unit is possible and very beneficial.Weather conditions may effect the power output of internal combustion engines. Therefore,established horsepower ratings refer to the power that the engine will produce at its ratedrpm under a specific combination of weather conditions.


Page 1A-10 90-861329--1 MARCH 1999


1B

MAINTENANCESERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 1B-1

IMPORTANT INFORMATIONSection 1B - Maintenance

Table of Contents

Maintenance Schedule 1B-2. . . . . . . . . . . . . . . . . Maintenance Intervals 1B-2. . . . . . . . . . . . . . . Scheduled Maintenance That Can Be Performed By Owner/Operator 1B-2. . . Scheduled Maintenance That Should Be Performed By A Dealer 1B-3. . . . . . . . . .

Engine and Tune-Up Specifications 1B-4. . . . . . Fluid Capacities 1B-5. . . . . . . . . . . . . . . . . . . . . . . Engine Rotation and Firing Order 1B-5. . . . . . . .

L.H. Rotation Front 1B-5. . . . . . . . . . . . . . . . . 20-Hour Break-In Period 1B-5. . . . . . . . . . . . . . . After Break-in Period 1B-6. . . . . . . . . . . . . . . . . . End of First Season Checkup 1B-6. . . . . . . . . . . Fuel 1B-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fuel Ratings 1B-6. . . . . . . . . . . . . . . . . . . . . . . General Information 1B-6. . . . . . . . . . . . . . . . . Gasoline / Alcohol Blends 1B-7. . . . . . . . . . . . Effects of Gasoline / Alcohol Blends on Marine Engines 1B-7. . . . . . . . . . . . . . . . . Boat / Motor Storage 1B-8. . . . . . . . . . . . . . . . Winter Storage 1B-8. . . . . . . . . . . . . . . . . . . . . Warranty 1B-8. . . . . . . . . . . . . . . . . . . . . . . . . . Continuing Evaluations 1B-8. . . . . . . . . . . . . . Test For Alcohol Content In Gasoline 1B-8. .

Crankcase Oil 1B-9. . . . . . . . . . . . . . . . . . . . . . . . Overfilled Crankcase Oil 1B-9. . . . . . . . . . . . . Adding Crankcase Oil 1B-10. . . . . . . . . . . . . . Checking Engine Oil Level/Filling 1B-10. . . .

Changing Oil and Filter 1B-11. . . . . . . . . . . . . . . . Priming Engines With Oil 1B-11. . . . . . . . . . . . . .

Tools Required 1B-11. . . . . . . . . . . . . . . . . . . . Procedure 1B-11. . . . . . . . . . . . . . . . . . . . . . . .

Power Steering System 1B-12. . . . . . . . . . . . . . . Checking Fluid Level 1B-12. . . . . . . . . . . . . . . Filling and Bleeding 1B-13. . . . . . . . . . . . . . . .

Closed Cooling System 1B-14. . . . . . . . . . . . . . . Checking Coolant Level 1B-14. . . . . . . . . . . . Coolant for Closed Cooling System 1B-14. . Flushing System 1B-15. . . . . . . . . . . . . . . . . . .

Lubrication 1B-17. . . . . . . . . . . . . . . . . . . . . . . . . . Throttle Cable 1B-17. . . . . . . . . . . . . . . . . . . . . Shift Cable 1B-18. . . . . . . . . . . . . . . . . . . . . . . . Engine Coupler / U-Joint Shaft Splines 1B-18. . . . . . . . . . . . . . . . . . . . . . . . . .

Cold Weather or Extended Storage 1B-19. . . . . Precautions 1B-19. . . . . . . . . . . . . . . . . . . . . . . Power Package Layup 1B-20. . . . . . . . . . . . .

Draining Instructions 1B-21. . . . . . . . . . . . . . . . . . Single Point Drain System 1B-21. . . . . . . . . . Draining Seawater (Raw-Water) Cooled Models 1B-23. . . . . . . . . . . . . . . . . . . Draining Seawater Section of Closed Cooled (Coolant) Models 1B-26. . . . . . . . . . Recommissioning 1B-28. . . . . . . . . . . . . . . . . .

MAINTENANCE SERVICE MANUAL NUMBER 26

Page 1B-2 90-861329--1 MARCH 1999

Maintenance Schedule

Maintenance IntervalsMaintenance intervals and the tasks to be performed, as shown in this current schedule, oras found in previously printed schedules, are generally based on an average boatingapplication and environment. However, individual operating habits and personal mainte-nance preferences can have an impact on the suggested intervals. In consideration of thesefactors, MerCruiser has adjusted some maintenance intervals and corresponding tasks tobe performed. In some cases, this may allow for more individual tasks to be performed ina single visit to the servicing dealer, rather than multiple visits. Therefore, it is very importantthat the boat owner and servicing dealer discuss the current Maintenance Schedule anddevelop appropriate maintenance intervals to coincide with the individual operating habits,environment and maintenance requirements.

Scheduled Maintenance That Can Be Performed By Owner/OperatorNOTE: Only perform maintenance which applies to your particular power package.

Task Interval

Engine Crankcase Oil - Check level.

Closed Cooling Coolant - Check level.

Power Steering Fluid - Check level.

Sterndrive Unit Oil - Check level.

Battery - Check level and inspect fordamage.

Fuel Pump Sight Tube (If Equipped) - Checkthat no fuel is present.

Weekly

Power Trim Pump Oil - Check level.

Anodes - Inspect for erosion.

Gear Housing Water Pickups - Check formarine growth or debris.

Drive Belts (All) - Inspect condition andcheck tension.

Every 100 hours of operation or 120 days,whichever occurs first.

Propeller Shaft - Lubricate. Saltwater Use: Every 50 hours of operationor 60 days, whichever occurs first.

Power Package Exterior Surfaces - Spraywith rust preventative.

Freshwater Use: Every 100 hours ofoperation or 120 days, whichever occursfirst.

Power Package Exterior Surfaces - Cleanand paint.

Once a year

Cooling System - Flush seawater section. Saltwater Use: After every use.


90-861329--1 MARCH 1999 Page 1B-3

Scheduled Maintenance That Should Be Performed By A DealerNOTE: Only perform maintenance which applies to your particular power package.

Task Interval

Seawater Pickup Pump - Disassemble andinspect.

Whenever insufficient seawater flow issuspected (if operating temperatureexceeds normal range.)

Crankcase Oil and Filter - Change.

Ignition System - Clean and inspectcondition.

Flame Arrestor and Crankcase VentilationHose - Clean and inspect.

Positive Crankcase Ventilation (PCV) Valve(If Equipped) - Change.

Sterndrive Unit Oil - Change.

Gimbal Ring Clamping Screws - Retorqueto 50-55 lb-ft (67-74 Nm).

Rear Engine Mounts - Check, torque to38 lb-ft (52 Nm).

Gimbal Bearing - Lubricate.

Cooling System - Clean and inspect.

Steering System - Lubricate and inspect forloose, damaged or missing parts. End of first boating season and thereafter,

Electrical System - Check for loose ordamaged wiring.

every 100 hours of operation or once yearly,whichever occurs first.

Closed Cooling System Pressure Cap -Clean, inspect and test.

Cooling System Hoses and Clamps -Inspect for damage and deterioration.Check clamps for tightness.

Continuity Circuit - Check components forloose connections, broken or frayed wires.

Shift and Throttle Cable and Linkage -Lubricate and inspect for loose, damaged ormissing parts.

Engine Exhaust System - Inspect externallyfor damage, deterioration and restrictions.Check for tightness.

Ignition System - Check timing and adjustas needed.

Closed Cooling Coolant - Replace. Every 5 years or 1000 hours, whicheveroccurs first1

1Only if Extended Life 5/100 Ethylene Glycol Antifreeze/Coolant is used. If any non-compatible coolant is addedto this coolant, coolant must be changed every 2 years or 400 hours, whichever occurs first. All coolants otherthan Extended Life 5/100 Ethylene Glycol Antifreeze/Coolant must be changed every 2 years or 400 hours,whichever occurs first.


Page 1B-4 90-861329--1 MARCH 1999

Engine and Tune-Up Specifications

MODEL MCM 3.0L

Propshaft Horsepower

(SAV1 Rating)

1351

(1142)

Propshaft Kilowatts

(SAV1 Rating)

1011

(852)

Number of Cylinders 4

Displacement 181 cid (3.0L)

Bore/Stroke In. (mm) 4.00 X 3.60 (101.6 X 91.4)

Compression Ratio 9.25:1

Compression Pressure Minimum 100 psi (690 kPa)7

Idle rpm (In Neutral)3 700 rpm5

Max rpm (At W.O.T.)3 4400-4800 rpm

Oil Pressure (at 2000 rpm) Minimum 30 psi (207 kPa)

Fuel Pump psi (At 1000 rpm) 6-8 psi (41-55 kPa)

Minimum Oil Pressure At Idle 4 psi (28 kPa)

Electrical System 12 Volt Negative (-) Ground

Minimum Battery Requirements 375 cca / 475 mca / 90 Ah

Firing Order 1-3-4-2

Spark Plug TypeAC - MR43LTS

Champion - RS12YC

NGK - BPR6EFS

Spark Plug Gap .035 in. (0.9 mm)

Timing (At Idle)4 1° BTDC8 / 1° ATDC9 / 2° ATDC10

Preliminary Idle Mixture 1 1/4 Turns

Thermostat 143° F (62° C)8 / 160° F(71° C)10

1 Power Rated in Accordance with NMMA (National Marine Manufacturers’ Association) rating procedures.2 Power Rated in Accordance with SAV1 rating procedures. This rating procedure is used to certify that the en-gine complies with “Stage 1” Bodensee and Swiss Regulations. Horsepower differences shown result from dif-ferences in test rpm, allowable test tolerances, and/or installation of special kit components.3 Measured using an accurate service tachometer with engine at normal operating temperature.4 Timing must be set using a special procedure as outlined in the appropriate section of this manual. Timing can-not be properly set using the conventional method.5 A special procedure must be followed to adjust idle rpm. Consult your Authorized MerCruiser Dealer beforeattempting this procedure.7 Minimum recorded compression in any one cylinder should not be less than 70 percent of the highest recordedcylinder.8Serial number break: 0L096999 and below9Serial number break: 0L097000 - 0L034099910Serial number break: 0L341000 and above.


90-861329--1 MARCH 1999 Page 1B-5

Fluid Capacities

NOTICE

Unit Of Measurement: U.S. Quarts (Liters)All capacities are approximate fluid measures.

MODEL MCM 181 cid / 3.0L

Crankcase (With Filter) 1 4 (3.8)

Seawater Cooling System 2 9 (8.5)

Closed Cooling System 9 (8.5)

1 Always use dipstick to determine exact quantity of oil or fluid required.2 Seawater Cooling System capacity information is for winterization use only.

Engine Rotation and Firing Order

L.H. Rotation Front

50683

4 Cylinder - 181 cid / 3.0L Firing Order 1-3-4-2

20-Hour Break-In Period

IMPORTANT: The first 20 hours of operation is the engine break-in period. Correctbreak-in is essential to obtain minimum oil consumption and maximum engine per-formance. During this break-in period, the following rules must be observed:

• Do not operate below 1500 rpm for extended periods of time for first 10 hours. Shift intogear as soon as possible after starting and advance throttle above 1500 rpm if condi-tions permit safe operation.

• Do not operate at one speed consistently for extended periods.

• Do not exceed 3/4 throttle during first 10 hours. During next 10 hours, occasionaloperation at full throttle is permissible (5 minutes at a time maximum).

• Avoid full throttle acceleration from IDLE speed.

• Do not operate at full throttle until engine reaches normal operating temperature.


Page 1B-6 90-861329--1 MARCH 1999

After Break-in Period

To help extend the life of your MerCruiser power package, the following recommendationsshould be considered;

• Use a propeller that allows the engine to operate at or near the top of the maximum rpmrange (See “Specifications” section) when at full throttle with a normal boat load.

• Operation at 3/4 throttle setting or lower is recommended. Refrain from prolongedoperation at maximum (full throttle) rpm.

End of First Season Checkup

At the end of the first season of operation, an Authorized MerCruiser Dealer should be con-tacted to discuss and/or perform various scheduled maintenance items. If you are in an areawhere the product is operated continuously (year-round operation), you should contact yourdealer at the end of the first 100 hours of operation, or once yearly, whichever occurs first.

Fuel

Fuel Ratings

CAUTIONUse of improper gasoline can damage the engine seriously. Engine damage thatresults from use of improper gasoline is considered misuse of the engine and is notcovered under MerCruiser Warranty.

USA AND CANADA

Fuel having a posted pump Octane Rating of 87 (R + M) / 2 minimum. Premium gasoline[90 (R + M) / 2] is also acceptable. DO NOT use leaded gasolines.

OUTSIDE USA AND CANADA

Fuel having a posted pump Octane Rating of 90 RON minimum. Premium gasoline (98RON) is also acceptable. If unleaded is not available, use a major brand of leaded gasoline.

General InformationGasolines containing alcohol, either methyl alcohol (methanol) or ethyl alcohol (ethanol)may cause increased:

• Corrosion of metal parts.

• Deterioration of elastomer and plastic parts.

• Fuel permeation through flexible fuel lines.

• Wear and damage of internal engine parts.

• Starting and operating difficulties.


90-861329--1 MARCH 1999 Page 1B-7

Some of these adverse effects are due to the tendency of gasolines containing alcohol toabsorb moisture from the air, resulting in a phase of water and alcohol separating from thegasoline in the fuel tank.

The adverse effects of alcohol are more severe with methyl alcohol (methanol) and areworse with increasing alcohol content.

WARNINGFire and Explosion Hazard: Fuel leakage from any part of the fuel system can be afire and explosion hazard which can cause serious bodily injury or death. Carefulperiodic inspection of the entire fuel system is mandatory, particularly afterstorage. All fuel system components including fuel tanks (whether plastic, metal orfiberglass), fuel lines, primer bulbs, fittings, fuel filters and carburetors should beinspected for leakage, softening, hardening, swelling or corrosion. Any sign ofleakage or deterioration requires replacement before further engine operation.

Because of possible adverse effects of alcohol in gasoline, it is recommended thatonly alcohol-free gasoline be used where possible. If only fuel containing alcoholis available, or if the presence of alcohol is unknown, increased inspectionfrequency for leaks and abnormalities is required.

WARNINGAvoid gasoline fire or explosion. Improper installation of brass fittings or plugs intofuel pump or fuel filter base can crack casting and/or cause a fuel leak.

IMPORTANT: When operating a MerCruiser engine on gasoline containing alcohol,storage of gasoline in the fuel tank for long periods should be avoided. Long periodsof storage, common to boats, create unique problems. In cars, alcohol-blend fuelsnormally are consumed before they can absorb enough moisture to cause trouble,but boats often sit idle long enough for phase separation to take place. In addition,internal corrosion may take place during storage if alcohol has washed protective oilfilms from internal components.

Gasoline / Alcohol BlendsMany new motor vehicle owner manuals are warning about the potential damage from usinggasoline containing alcohol, especially METHANOL. They cite possible fuel systemdamage and performance problems. These are just two of the hazards that may be causedby alcohol. These same problems as well as the additional safety risk of fire and explosionfrom fuel system leaks apply to marine inboard engines. METHANOL is more severe in itsbad effect than is ETHANOL. Alcohol is also more severe in older engines since newerengines have materials which are more resistant to alcohol.

Effects of Gasoline / Alcohol Blends on Marine EnginesCorrosion of metals may result from use of alcohol-gasoline blends. Portable orpermanently installed fuel tanks of metal or fiberglass, fuel filters, fuel lines and float bowlsmay be affected by alcohol blended fuels. Many fiberglass fuel tanks are slowly dissolvedby alcohol, leading immediately to filter and carburetor plugging and eventually to tankfailure.


Page 1B-8 90-861329--1 MARCH 1999

Fuels containing alcohol will absorb moisture from the air. At first, this moisture will remainin solution, but once the water content of the fuel has built up to about one-half of onepercent, it will separate out (phase separation), bringing the alcohol with it. Thisalcohol-water mixture settles to the bottom of the fuel tank and if this mixture gets into theengine, the engine can be seriously damaged internally, as it may wash the protective filmof oil off the bore of any cylinder that it enters. Before the engine can be restarted, it isnecessary to remove the separated alcohol and water layer, flush out the fuel system withclean fuel and remove and dry the spark plugs.

Boat / Motor StorageWhen operating a MerCruiser engine on gasoline containing alcohol, storage of gasolinein the fuel tank for long periods of time should be avoided.

Long periods of storage, common to boats, create unique problems. In cars,gasoline/alcohol blend fuels normally are consumed before they can absorb enoughmoisture to cause trouble, but boats often sit idle long enough for phase separation to takeplace. In addition, internal corrosion may take place during storage if alcohol has washedprotective oil films from internal components.

Winter StorageIf boat is to be placed in winter storage, carburetors must be run dry at idle rpm. Permanentfuel tanks should be drained completely and Quicksilver Gasoline Stabilizer andConditioner added to any fuel remaining in the tank. Portable fuel tanks should be emptiedcompletely.

WarrantyPerformance problems and fuel system or other damage resulting from the use ofgasoline-alcohol blended fuels are not the responsibility of MerCruiser and will not becovered under our warranty.

Continuing EvaluationsThe effects of gasoline with ETHANOL and METHANOL are still being evaluated by theUnited States Coast Guard, the National Marine Manufacturers Association (NMMA),Mercury Marine and other engine and boat manufacturers.

We have recommended pump posting of alcohol content of gasoline. Further we recom-mend using gasoline known not to contain any METHANOL or ETHANOL when possible.

Test For Alcohol Content In GasolineThe following is an acceptable and widely used field procedure for the detection of alcoholin gasoline. Use any small transparent bottle or tube that can be capped and is, or can be,provided with graduations or a mark at about 1/3 full. A pencil mark on a piece of adhesivetape may be used.

PROCEDURE

1. Fill the container with water to the mark.

2. Add fuel almost to fill the container, leaving some air space, then cap the container. Theproportions of fuel to water are not critical, but there should be 2 to 3 times as much fuelas water.

3. Shake container vigorously and allow it to sit upright for 3 to 5 minutes. If the volumeof water appears to have increased, alcohol is present. If you are not sure, there is noneed for concern. If the dividing line between water and fuel becomes cloudy, use themiddle of the cloudy band.


90-861329--1 MARCH 1999 Page 1B-9

Crankcase Oil

To help obtain optimum engine performance and to provide maximum protection, westrongly recommend the use of Quicksilver 4-Cycle 25W-40 Marine Engine Oil. This oil isa special blend of 25-weight and 40-weight oils for marine engines. If not available, a goodgrade, straight weight, detergent automotive oil of correct viscosity, with an API servicerating of SH,CF/CF-2 may be used.

In those areas where Quicksilver 4-Cycle 25W-40 Marine Engine Oil or a recommendedstraight weight oil is not available, a multi-viscosity 20W-40 or, as a second but lesspreferable choice, 20W-50, with API service ratings of SH,CF/CF-2 may be used.

IMPORTANT: The use of non-detergent oils, multi-viscosity oils (other thanQuicksilver 25W-40 or a good quality 20W-40 or 20W-50), synthetic oils, low qualityoils or oils that contain solid additives are specifically not recommended.

The chart below is a guide to crankcase oil selection. The oil filter should always be changedwith the engine oil.

SAE 20W

SAE 30W

SAE 40W

32° F0° C

50° F10° C

AIR TEMPERATURE75796

Overfilled Crankcase OilOverfilled crankcases (oil level being too high ) can cause a fluctuation or drop in oil pressureand rocker arm “clatter” on MerCruiser engines. The over-full condition results in the enginecrankshaft splashing and agitating the oil, causing it to foam (become aerated). The aeratedoil causes the hydraulic valve lifters to “bleed down.” This, in turn, results in rocker arm“clatter” and loss of engine performance, due to the valves not opening properly.

Care must be taken when checking engine oil level. Oil level must be maintained betweenthe ADD mark and the FULL mark on the dipstick. To ensure that you are not getting a “falsereading,” make sure the following steps are done before checking the oil level.

• Boat “at rest” in the water, or

• If boat is on a trailer, raise or lower bow until the boat is setting at the approximate anglethat it would be if setting “at rest” in the water.

• Allow sufficient time for oil to drain into the crankcase if engine has just been run or oilhas just been added.


Page 1B-10 90-861329--1 MARCH 1999

Adding Crankcase Oil1. Coat sealing ring on new filter with engine oil, and install. Tighten filter securely

(following filter manufacturer’s instructions). Do not overtighten.

75809

b

a

a - Oil Filterb - Sealing Ring

2. Fill crankcase with oil.

3. Start engine and check for leaks.

Checking Engine Oil Level/FillingIMPORTANT: ENGINE CRANKCASE OIL MUST BE CHECKED AT INTERVALSSPECIFIED IN “MAINTENANCE SCHEDULE” CHART. It is normal for an engine to usea certain amount of oil in the process of lubrication and cooling of the engine. Theamount of oil consumption is greatly dependent upon engine speed, withconsumption being highest at wide-open-throttle and decreasing substantially asengine speed is reduced.

1. Stop engine and allow boat to come to a rest.

2. Allow oil to drain back into oil pan - approximately 5 minutes.

3. Remove dipstick. Wipe clean and reinstall. Push dipstick all the way into dipstick tube.

4. Remove dipstick and note the oil level.

5. Oil level must be between the FULL and ADD marks.

6. If oil level is below ADD mark, proceed to Steps 7 and 8.

7. Remove oil filler cap from valve rocker arm cover.

8. Add required amount of oil to bring level up to, but not over, the FULL mark on dipstick.


90-861329--1 MARCH 1999 Page 1B-11

Changing Oil and Filter

1. Start engine and run until it reaches normal operating temperatures.

IMPORTANT: Change oil when engine is warm from operation, as it flows more freely,carrying away more impurities.

2. Stop engine.

3. Remove drain plug from oil pan or from oil drain hose.

NOTE: If drain plug is not accessible because of boat construction, oil may be removedthrough dipstick tube, using a Quicksilver Crankcase Oil Pump.

4. After oil has drained completely, reinstall drain plug (if removed) and tighten securely.

5. Remove and discard oil filter and its sealing ring.

Priming Engines With Oil

IMPORTANT: This applies to all power packages that have not been run within 6months, replacement of partial engines or after rebuilding an engine.

Tools Required

71089

Remote Starter Switch (91-52024A1)

Procedure1. Fill crankcase to proper level with recommended engine oil.

2. Remove spark plugs.

3. Leave ignition Key in “OFF” position.

4. Connect remote starter switch to large 12V terminal (RED battery cable) and smallterminal (RED/YELLOW) wire on starter motor.

a. If Remote Starter Switch is not available, disconnect PURPLE wire from ignition coilbefore using key switch to crank the engine over. Tape terminal on PURPLE wire toprevent it from touching ground.

5. Crank engine for 15 seconds, then allow starter motor to cool down for 1 minute. Thisshould prevent starter motor from overheating.

6. Repeat this process until a total of 45 seconds of cranking time is achieved.

7. Remove remote starter switch.

a. If key switch was used, reconnect PURPLE wire to ignition coil.

8. Install spark plugs and wires.

9. Supply cooling water to seawater pump and start motor.


Page 1B-12 90-861329--1 MARCH 1999

Power Steering System

Checking Fluid Level

ENGINE WARM

1. Stop engine and position drive unit so that it is straight back.

2. Remove fill cap/dipstick from power steering pump and note fluid level.

75809

a

b

a - Fill Cap / Dipstickb - Power Steering Pump

3. Level should be between the FULL HOT mark and ADD mark on dipstick.

72518a

a - Proper Fluid Level with Engine Warm

4. If level is below ADD mark, but fluid is still visible in pump reservoir, add required amountof Quicksilver Power Trim and Steering Fluid or automatic transmission fluid (ATF)Dexron III through fill cap opening, to bring level up to FULL HOT mark on dipstick. DONOT OVERFILL.

5. If fluid is not visible in reservoir, a leak exists in the power steering system. Find causeand correct.


90-861329--1 MARCH 1999 Page 1B-13

ENGINE COLD

1. With engine stopped, position drive unit so that it is straight back.


3. Level should be between FULL COLD mark and bottom of dipstick.

72519a

a - Proper Fluid Level with Engine Cold

4. If level is below bottom of dipstick, but fluid is still visible in pump reservoir, add requiredamount of Quicksilver Power Trim and Steering Fluid or automatic Dexron IIItransmission fluid (ATF), through fill cap opening, to bring level up to FULL COLD markon dipstick. DO NOT OVERFILL.

If fluid is not visible in reservoir, a leak exists in the power steering system. Find cause andcorrect.

Filling and BleedingIMPORTANT: Power steering system must be filled exactly as explained in the follow-ing to be sure that all air is bled from the system. All air must be removed, or fluid inpump may foam during operation and be discharged from pump reservoir. Foamyfluid also may cause power steering system to become spongy, which may result inpoor boat control.

1. With engine stopped, position drive unit so that it is straight back. Remove fillcap/dipstick from power steering pump. Add Quicksilver Power Trim and Steering Fluidor Dexron III automatic transmission fluid (ATF), as required, to bring level up to FULLCOLD mark on dipstick.

IMPORTANT: Use only Quicksilver Power Trim and Steering Fluid or Dexron IIl auto-matic transmission fluid (ATF), in power steering system.

2. Turn steering wheel back and forth to end of travel in each direction several times, thenrecheck fluid level and add fluid, if necessary.

3. Install vented fill cap.

CAUTIONDO NOT operate engine without water being supplied to seawater pickup pump, orpump impeller may be damaged and subsequent overheating damage to enginemay result.

4. Start engine and run at fast idle (1000-1500 rpm) until engine reaches normal operatingtemperature. During this time, turn steering wheel back and forth to end of travel in eachdirection several times.


Page 1B-14 90-861329--1 MARCH 1999

5. Position drive unit so that it is straight back and stop engine. Remove fill cap from pump.Allow any foam in pump reservoir to disperse, then check fluid level and add fluid, asrequired, to bring level up to FULL HOT mark on dipstick. DO NOT OVERFILL. Reinstallfill cap securely.

IMPORTANT: Drive unit must be positioned straight back and power steering fluidmust be hot to accurately check fluid level.

6. If fluid is still foamy (in Step 5), repeat Steps 4 and 5 until fluid does not foam and levelremains constant.

Closed Cooling System

Checking Coolant Level

WARNINGAllow engine to cool down before removing pressure cap. Sudden loss of pressurecould cause hot coolant to boil and discharge violently. After engine has cooled,turn cap 1/4 turn to allow any pressure to escape slowly, then push down and turncap all the way off.

1. Coolant level in heat exchanger should be full (to bottom of filler neck).

IMPORTANT: When reinstalling pressure cap, be sure to tighten it until it contactsstop on filler neck.

2. Coolant level should be between the ADD and FULL marks on coolant recoveryreservoir with the engine at normal operating temperature.

193-HR

a

a - Coolant Recovery Reservoir

Coolant for Closed Cooling System

CAUTIONAlcohol or Methanol base antifreeze or plain water, are not recommended for usein fresh water section of cooling system at any time.

We recommend that the coolant section of closed cooling system be filled with ExtendedLife 5/100 Ethylene Glycol Antifreeze/Coolant. In areas where the possibility of freezingdoes not exist, it is permissible to use a solution of rust inhibitor and water (mixed tomanufacturer’s recommendations).


90-861329--1 MARCH 1999 Page 1B-15

Flushing SystemIf engine is operated in salty, polluted, or mineral-laden water, flush cooling system (prefer-ably after each use) to reduce corrosion and prevent the accumulation of deposits in thesystem. Thoroughly flush cooling system prior to storage.

BOAT OUT OF WATER

WARNINGWhen flushing cooling system with boat out of the water, be certain that area invicinity of propeller is clear and that no person is standing nearby. As aprecautionary measure, it is recommended that propeller be removed.

CAUTIONTo prevent engine or sterndrive unit damage DO NOT run engine or drive unit with-out water being supplied to water intake openings on gear housing, and to seawaterpickup pump if equipped.

1. Connect flushing attachment as follows:

NOTE: If flushing cooling system with boat in water, raise drive unit to trailer position andinstall flushing attachment. Lower drive unit to full IN/DOWN position.

a. Install Quicksilver Flushing Attachment (or equivalent) over water intake openingsin gear housing.

b. Connect hose between flushing attachment and water tap.

72012

a

b

a - Quicksilver Flushing Attachmentb - Water Hose

CAUTIONIf cooling system is to be flushed with boat in the water, seacock (if equipped) mustbe closed, or water inlet hose must be disconnected and plugged to prevent waterfrom flowing into boat.


Page 1B-16 90-861329--1 MARCH 1999

2. Partially open water tap(s) (approximately 1/2 maximum capacity) and allow drive unitand cooling system to fill completely. Do not use full tap water pressure.

72672

a

b

a - Quicksilver Flushing Attachmentb - Water To Drive Unit

NOTE: Drive unit is full when water is discharged out of drive unit, and/or seawater sectionof closed cooled system is full when water is discharged through propeller.

CAUTIONDo not run engine above 1500 rpm when flushing. Suction created by seawater pick-up pump may collapse flushing hose, causing engine to overheat.

3. Place remote control lever in NEUTRAL position and start the engine.

CAUTIONWatch temperature gauge at dash to ensure the engine does not overheat.

4. Operate engine at idle speed in NEUTRAL gear for 10 minutes or until discharge wateris clear, then stop engine.

5. Shut off water tap(s).

6. Remove hose and flushing attachment from drive unit.

BOAT IN WATER

NOTE: If flushing cooling system with boat in water, raise drive unit to trailer position, toremove flushing attachment. Lower drive unit to full IN/DOWN position after completion.

1. Raise drive unit to full UP (trailer) position.

2. Install flushing attachment over water pickup holes in gear housing as shown.

3. Attach a hose between the flushing attachment and a water tap.

4. Lower drive unit to full IN/DOWN position.

5. Partially open water tap (approximately 1/2 maximum capacity). Do Not use full waterpressure.

6. Place remote control in neutral, idle speed position, and start engine.

7. Operate engine at idle speed in neutral for 10 minutes, the stop engine.

8. Shut off water tap.


90-861329--1 MARCH 1999 Page 1B-17

9. Raise drive unit to full UP position.

10. Remove hose and flushing attachment.

CAUTIONIf boat is in the water, seacock (water inlet valve), if equipped, must remain closeduntil engine is to be restarted to prevent water from flowing back into coolingsystem and/or boat. If boat is not fitted with a seacock, water inlet hose must bedisconnected and plugged to prevent water from flowing back into cooling systemand/or boat. As a precautionary measure, attach a tag to the ignition switch orsteering wheel of the boat with the warning that the seacock must be opened or thewater inlet hose reconnected prior to starting engine.

a. If equipped with seacock: Observing precaution above, open seacock.

b. If NOT equipped with seacock: Observing precaution above, remove plug fromseawater inlet hose and reconnect seawater inlet hose. Tighten hose clampssecurely.

Lubrication

Lubricate pivot points with SAE 30W motor oil and cable guide contact surfaces withQuicksilver 2-4-C Marine Lubricant with Teflon.

Throttle Cable

75811

a

a - Pivot Points


Page 1B-18 90-861329--1 MARCH 1999

Shift Cable

75811

b

a b

a - Pivot Pointsb - Guide Contact Surface

Engine Coupler / U-Joint Shaft SplinesLubricate coupler and splines with Quicksilver Engine Coupler Spline Grease(92-816391A4).

IMPORTANT: Sterndrive unit does not have to be removed to grease coupler.

NOTE: Refer to MerCruiser Sterndrive Service Manual for sterndrive unit removal andinstallation if necessary.

72017

b

a

a - Quicksilver Engine Coupler Spline Greaseb - Grease Fitting, Use If Drive Is Installed


90-861329--1 MARCH 1999 Page 1B-19

Cold Weather or Extended Storage

Precautions

CAUTIONSterndrive unit should be stored in full DOWN position. Universal Joint bellows maydevelop a “set” if unit is stored in raised position and may fail when unit is returnedto service.

CAUTIONIf Power Package will not be used for an extended period of time or will be exposedto freezing temperatures, drain water from seawater section of cooling system. Wa-ter MUST BE drained to prevent corrosion and freeze damage to engine.

CAUTIONIf boat is to remain in water after draining, seawater inlet hose must be removed andplugged. The plug will prevent a siphoning action that may occur, allowing seawaterto flow from the drain holes or removed hoses.

CAUTIONDO NOT operate engine without water flowing through seawater pickup pump, aspump impeller may be damaged and subsequent overheating damage to engine orsterndrive unit may result.

CAUTIONSeawater section of cooling system MUST BE COMPLETELY drained for winterstorage, or immediately after cold weather use, if the possibility of freezing temper-atures exists. Failure to comply may result in trapped water causing freeze and/orcorrosion damage to engine.

IMPORTANT: Observe the following information to ensure complete draining ofcooling system:

• Engine must be as level as possible.

• A wire should be repeatedly inserted into all drain holes to ensure there are noobstructions in passages. Remove petcock, if necessary, to insert wire complete-ly into drain hole.

IMPORTANT: To prevent threads in manifolds, elbows and cylinder blocks from rust-ing out during storage, reinstall plugs using Quicksilver Perfect Seal on threads.Never leave drain plugs out during storage.

NOTE: If possible, place a container under drains and hoses to prevent water from draininginto boat.

CAUTIONIf engine is equipped with Closed Cooling System, Closed Cooling section must bekept filled with a solution of ethylene glycol antifreeze and water (mix antifreeze tomanufacturer’s recommended proportions to protect engine to lowest temperatureto which it will be exposed). DO NOT USE PROPYLENE GLYCOL antifreeze in closedcooling section. Seawater section, however, must be drained completely.


Page 1B-20 90-861329--1 MARCH 1999

CAUTIONA discharged battery can be damaged by freezing.

IMPORTANT: MerCruiser recommends that propylene glycol antifreeze (a nontoxicand environmentally safe) antifreeze be used in seawater section of the cooling sys-tem for cold weather or extended storage. Make sure that the propylene glycol anti-freeze contains a rust inhibitor and is recommended for use in marine engines. Becertain to follow the propylene glycol manufacturer’s recommendations.

Power Package Layup

CARBURETED MODELS

NOTICE

Refer to “Cold Weather or Extended Storage Precautions” in this section,BEFORE proceeding.

1. Follow instructions “a” or “b” depending on type fuel available during layup:

a. If boat is to be placed in storage with fuel in fuel tanks that does not containalcohol: Fill fuel tank(s) with fresh gasoline that does not contain alcohol and asufficient amount of Quicksilver Gasoline Stabilizer for Marine Engines to treat thegasoline. Follow instructions on container.

b. If boat is to be placed in storage with fuel in fuel tanks that does containalcohol (if fuel without alcohol is unavailable): Fuel tanks should be drained ascompletely as possible and Quicksilver Gasoline Stabilizer for Marine Enginesadded to any fuel remaining in the tank. Follow instructions on container.

IMPORTANT: If boat is to be placed in storage with fuel containing alcohol in fueltanks refer to “Fuel” in this SECTION 1B for additional information.

2. Replace the water separating fuel filter as outlined in SECTION 5A - Fuel DeliverySystems, “Water Separating Fuel Filter.”

3. Supply water to the seawater pickup pump as outlined in “Flushing Cooling System.”

4. Start the engine and check for fuel leaks. If leaks exist, stop the engine immediately.Recheck filter installation.

5. Start the engine. Operate at idle rpm until it reaches normal operating temperature andthe fuel stabilizer has been circulated. Shut off the engine.

6. Change the engine oil and filter.

7. If boat has been operated in salty, polluted or mineral-laden waters, flush cooling systemas outlined in “Flushing Cooling System.”

8. Prepare fuel system for extended storage as follows:

a. Close the fuel shut-off valve, if equipped. If no fuel shut off valve is present, a suitablemethod must be employed to STOP the flow of fuel from the fuel tank to the enginebefore proceeding.

b. Remove flame arrestor assembly and start engine.

c. While operating engine at fast idle (1000-1500 rpm), fog internal surfaces of induc-tion system and combustion chambers by squirting approximately 8 ounces (227grams) of Quicksilver Storage Seal or SAE 20W engine oil into carburetor bores.


90-861329--1 MARCH 1999 Page 1B-21

d. Squirt the remaining 2 ounces (57 g) of Storage Seal (or oil) rapidly into carburetor,just as the engine begins to stall, due to lack of fuel. Allow engine to stop.

e. Turn ignition key to OFF position.

f. Refer to “Flushing Cooling System” and appropriately remove water supply to theseawater pickup pump.

9. Clean flame arrestor and crankcase ventilation hoses and reinstall.

10. Drain seawater section of cooling system as outlined in “Draining Instructions.”

11. Closed Cooling System Models: Test coolant to ensure that it will protect againstfreezing to the lowest temperature expected during storage.

12. Lubricate all items outlined in “Lubrication.”

13. Service batteries. Refer to manufacturer’s instructions.

14. Clean outside of engine and repaint any areas required with Quicksilver Primer andSpray Paint. After paint has dried, spray Quicksilver Corrosion and Rust PreventiveType II or wipe down with Quicksilver Storage Seal or SAE 20W engine oil.

15. For drive unit layup information, refer to appropriate Sterndrive Manual.

CAUTIONSterndrive unit should be stored in full “down” position. Universal Joint bellowsmay develop a “set” if unit is stored in raised position and may fail when unit isreturned to service.

Draining Instructions

Single Point Drain SystemSome models are equipped with a single point drain system consisting of 2 hoses with hard-ware and a T-handle retrieval tool (shown below). This system drains the seawater sectionof the engine only.

76242

a

b

a - T-handle Retrieval Toolb - Hoses


Page 1B-22 90-861329--1 MARCH 1999

If your engine is equipped with this device, follow this procedure:

1. Detach the hoses from the top fittings.

76243

a

a - Fittings

2. Lower hoses into bilge. If hoses have developed a “set,” T-handle retrieval tool can beused to push hoses below their connection point.

76244

a b

a - Hosesb - Connection Points

IMPORTANT: Hoses must be lowered below their connection point on the engine inorder to drain completely.

3. If hoses do not drain, use wire to remove blockage.

4. Pull hoses back into original position after draining is complete. Reconnect to fittings.


90-861329--1 MARCH 1999 Page 1B-23

Draining Seawater (Raw-Water) Cooled Models

NOTICE


1. Engine must be as level as possible to ensure complete draining of cooling system.

2. Remove drain plugs from cylinder block and manifold.

71424

a

a - Drain Plug (Port and Starboard)

3. Repeatedly clean out drain holes using a stiff piece of wire. Do this until entire systemis drained.

NOTE: It may be necessary to lift, bend or lower hoses to allow water to drain completelywhen hoses are disconnected.

4. Remove and lower the hoses to allow them to drain.

75815

b

a

a - Inlet Hoseb - Circulating Pump Hose


Page 1B-24 90-861329--1 MARCH 1999

5. Insert a small wire (repeatedly) to make sure that vent holes and water drain holes andpassages (as shown) are unobstructed and open.

71216

70134

d

a

c

f

be

cf

a - Speedometer Pitot Tubeb - Gear Housing Cavity Drain Holec - Trim Tab Cavity Vent Holed - Trim Tab Cavity Drain Passagee - Gear Housing Water Drain Hole (One Each - Port and Starboard)f - Gear Housing Cavity Vent Hole

6. Crank engine over SLIGHTLY, with starter motor, to purge any water trapped in seawa-ter pickup pump. DO NOT ALLOW ENGINE TO START.

CAUTIONIf boat is in the water or is to remain in the water, seacock (if equipped) must remainclosed until engine is to be restarted, to prevent water from flowing back intocooling system. If boat is not fitted with a seacock, seawater inlet hose must remaindisconnected and plugged, to prevent water from flowing into cooling systemand/or boat. As a precautionary measure, attach a tag to the ignition switch orsteering wheel with the warning that the seacock must be opened or the seawaterinlet hose reconnected prior to starting the engine.

7. After cooling system has been drained completely, coat threads of drain plugs withQuicksilver Perfect Seal and reinstall. Tighten drain plugs securely. Reconnect hosesand tighten all hose clamps securely. If NOT equipped with seacock: seawater inlethose must remain disconnected and plugged until engine is to be restarted.

IMPORTANT: MerCruiser recommends that propylene glycol antifreeze (nontoxicand biodegradable, which makes it friendly to lakes and rivers) be used in seawatersection of the cooling system for cold weather or extended storage. Make sure thatthe propylene glycol antifreeze contains a rust inhibitor and is recommended for usein marine engines. Be certain to follow the propylene glycol manufacturer’s recom-mendations.


90-861329--1 MARCH 1999 Page 1B-25

8. For additional assurance against freezing and rust, remove the thermostat cover andthermostat. Fill the engine seawater cooling system with a mixture of antifreeze and tapwater mixed to manufacturer’s recommendation to protect engine to the lowest temper-ature to which it will be exposed during cold weather or extended storage. Using a newgasket, reinstall thermostat and cover. Tighten cover bolts to 30 lb-ft (41 Nm).

72589

a

b

c

d

e

f

g

76246

b

c

d

c

g

a - Lifting Eyeb - Coverc - Gasketd - Hosee - Thermostatf - Fittingg - Housing

NOTE: Hoses shown removed only to indicate flow. Do not remove hoses.


Page 1B-26 90-861329--1 MARCH 1999

Draining Seawater Section of Closed Cooled (Coolant) Models

NOTICE


CAUTIONIf boat is in the water or is to remain in the water, seacock (if equipped) must remainclosed until engine is to be restarted to prevent contaminated water from flowingback into cooling system. If boat is not fitted with a seacock, water inlet hose mustbe left disconnected and plugged to prevent contaminated water from flowing intocooling system and/or boat. As a precautionary measure, attach a tag to the ignitionswitch or steering wheel with the warning that the seacock must be opened or thewater inlet hose reconnected prior to starting the engine.

1. Ensure engine is as level as possible to ensure complete draining of cooling system.

2. Remove drain plug from the following locations:

a. Aft (rear) drain plug from the heat exchanger.

73581a

a- Heat Exchanger Drain Plug

b. Bottom of exhaust manifold.

75177

a

a- Exhaust Manifold Drain Plug


90-861329--1 MARCH 1999 Page 1B-27


NOTE: It may be necessary to lift or bend hoses to allow water to drain completely.

4. Make sure gear housing water vent and drain holes, speedometer pitot hole and trimtab cavity vent and drain holes are open and unobstructed.

71216

d

b

a

c

a- Vent Holesb- Anode Cavity Drain Holesc- Drain Holed- Speedometer Pitot Hole

5. Crank engine over,slightly with starter motor to purge any water trapped in seawaterpickup pump. Do not allow engine to start.

6. After cooling system has been drained completely, install drain plugs, reconnect hosesand tighten all hose clamps securely.


Page 1B-28 90-861329--1 MARCH 1999

Recommissioning

NOTICE

Refer to “Cold Weather or Extended Storage Precautions” in this sectionBEFORE proceeding.

WARNINGTo prevent possible injury or damage to equipment, do not install battery until allmaintenance has been performed on engine.

1. Check that all cooling system hoses are connected properly and hose clamps are tight.Check that all drain plugs are installed and tightened securely.

2. Inspect drive belts.

CAUTIONWhen installing battery, be sure to connect NEGATIVE (–) battery cable toNEGATIVE (–) battery terminal and POSITIVE (+) battery cable to POSITIVE (+)battery terminal. If battery cables are reversed, electrical system damage will result.

3. Install fully-charged battery. Clean battery cable clamps and terminals and reconnectcables (see CAUTION listed above). Tighten each cable clamp securely whenconnecting.

4. Coat terminal connections with a battery terminal anti-corrosion agent.

5. Perform all maintenance tasks listed in the MAINTENANCE SCHEDULES, exceptthose performed during the power package lay up procedure.

6. Perform all checks in the BEFORE STARTING column of the Operation andMaintenance Manual OPERATION CHART.

CAUTIONRefer to FLUSHING COOLING SYSTEM before starting engine.


8. Start engine and closely observe instrumentation to make sure that all systems arefunctioning correctly.

9. Carefully inspect engine for fuel, oil, fluid, water and exhaust leaks.

10. Check steering system and shift and throttle controls for proper operation.

11. For drive unit, refer to appropriate sterndrive manual.


90-861329--1 MARCH 1999 Page 1B-29



Page 1B-30 90-861329--1 MARCH 1999


1C

TROUBLESHOOTINGSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 1C-1

IMPORTANT INFORMATIONSection 1C - Troubleshooting

Table of Contents

Precautions 1C-2. . . . . . . . . . . . . . . . . . . . . . . . . . Used Spark Plug Analysis 1C-3. . . . . . . . . . . . . . Spark Plug Analysis 1C-4. . . . . . . . . . . . . . . . . . .

Normal Condition 1C-4. . . . . . . . . . . . . . . . . . . Chipped Insulator 1C-4. . . . . . . . . . . . . . . . . . . Wet Fouling (Oil Deposits) 1C-4. . . . . . . . . . . Cold Fouling 1C-5. . . . . . . . . . . . . . . . . . . . . . . Overheating 1C-5. . . . . . . . . . . . . . . . . . . . . . . High Speed Glazing 1C-5. . . . . . . . . . . . . . . . . Scavenger Deposits 1C-6. . . . . . . . . . . . . . . . Pre-Ignition Damage 1C-6. . . . . . . . . . . . . . . . Reversed Coil Polarity 1C-6. . . . . . . . . . . . . . . Splashed Deposits 1C-7. . . . . . . . . . . . . . . . . . Mechanical Damage 1C-7. . . . . . . . . . . . . . . .

Poor Boat Performance and/or Poor Maneuverability 1C-8. . . . . . . . . . . . . . . . . . . . . . Improper Full Throttle Engine RPM 1C-9. . . . . .

RPM Too High 1C-9. . . . . . . . . . . . . . . . . . . . . RPM Too Low 1C-9. . . . . . . . . . . . . . . . . . . . . .

Engine Cranks Over But Will Not Start Or Is Hard To Start 1C-10. . . . . . . . . . . . . . . . . .

Important Information 1C-10. . . . . . . . . . . . . . EST Ignition System Check 1C-11. . . . . . . . . . . .

Test Description 1C-11. . . . . . . . . . . . . . . . . . . Ignition System Check 1C-12. . . . . . . . . . . . .

Engine Will Not Crank Over/Starter Inoperative 1C-14. . . . . . . . . . . . . . . . . . . . . . . . . Charging System Inoperative 1C-14. . . . . . . . . . Noisy Alternator 1C-15. . . . . . . . . . . . . . . . . . . . . . Fuel System Rich 1C-15. . . . . . . . . . . . . . . . . . . . Fuel System Lean 1C-16. . . . . . . . . . . . . . . . . . . . Carburetor Malfunction 1C-16. . . . . . . . . . . . . . . .

Engine Runs Poorly At Idle 1C-18. . . . . . . . . . . . Engine Acceleration Is Poor 1C-19. . . . . . . . . . . Engine Runs Poorly At High RPM 1C-19. . . . . . Poor Fuel Economy 1C-20. . . . . . . . . . . . . . . . . . Radio Noise 1C-21. . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting With Vacuum Gauge 1C-21. . . Miscellaneous 1C-21. . . . . . . . . . . . . . . . . . . . . . . Instrumentation Malfunction 1C-22. . . . . . . . . . . Engine Noise 1C-22. . . . . . . . . . . . . . . . . . . . . . . .

Important Information 1C-22. . . . . . . . . . . . . . Valve Cover Area 1C-23. . . . . . . . . . . . . . . . . . Cylinder Area 1C-23. . . . . . . . . . . . . . . . . . . . . Camshaft Area 1C-23. . . . . . . . . . . . . . . . . . . . Crankshaft Area 1C-24. . . . . . . . . . . . . . . . . . . Miscellaneous 1C-25. . . . . . . . . . . . . . . . . . . . .

Oil Pressure 1C-26. . . . . . . . . . . . . . . . . . . . . . . . . Miscellaneous 1C-26. . . . . . . . . . . . . . . . . . . . . Low Oil Pressure 1C-27. . . . . . . . . . . . . . . . . . High Oil Pressure 1C-27. . . . . . . . . . . . . . . . . . Excessive Oil Consumption 1C-28. . . . . . . . .

Water in Engine 1C-29. . . . . . . . . . . . . . . . . . . . . . Important Information 1C-29. . . . . . . . . . . . . . Water In Crankcase 1C-29. . . . . . . . . . . . . . . . Water On Top Of Pistons 1C-30. . . . . . . . . . .

Engine Overheats 1C-31. . . . . . . . . . . . . . . . . . . . Mechanical 1C-31. . . . . . . . . . . . . . . . . . . . . . . Cooling System 1C-32. . . . . . . . . . . . . . . . . . .

Power Steering 1C-33. . . . . . . . . . . . . . . . . . . . . . Poor, Erratic or No Assist 1C-33. . . . . . . . . . . Noisy Pump 1C-34. . . . . . . . . . . . . . . . . . . . . . . Fluid Leaks 1C-34. . . . . . . . . . . . . . . . . . . . . . .

Insufficient Water Flow From Alpha One Sterndrive Unit Seawater Pickup Pump 1C-35

TROUBLESHOOTING SERVICE MANUAL NUMBER 26

Page 1C-2 90-861329--1 MARCH 1999

Precautions

WARNINGAlways disconnect battery cables from battery BEFORE working on fuel system toprevent fire or explosion.

WARNINGBe careful when cleaning flame arrestor and crankcase ventilation hose; gasolineis extremely flammable and highly explosive under certain conditions. Be sure thatignition key is OFF. DO NOT smoke or allow sources of spark or open flame in areawhen cleaning flame arrestor and crankcase ventilation hose.

WARNINGBe careful when changing fuel system components; gasoline is extremely flam-mable and highly explosive under certain conditions. Be sure that ignition key isOFF. DO NOT smoke or allow sources of spark or flame in the area while changingfuel filter. Wipe up any spilled fuel immediately.

WARNINGAvoid gasoline fire or explosion. Improper installation of brass fittings or plugs intofuel pump or fuel filter base can crack casting and/or cause a fuel leak. Followspecific procedure, given in Section 5 of this manual, for all fuel line connections.

WARNINGMake sure no fuel leaks exist before closing engine hatch.

CAUTIONDO NOT operate engine without cooling water being supplied to water pickup holesin gear housing, or water pump impeller will be damaged and subsequentoverheating damage may result.

CAUTIONDO NOT operate engine without water being supplied to seawater pickup pump onengine, or pump impeller may be damaged and subsequent overheating damage toengine may result. Engine may be operated with boat out of water, if instructionsunder “Running Engine with Boat Out of Water,” following, are completed.


90-861329--1 MARCH 1999 Page 1C-3

WARNINGWhen running engine with boat out of water, be certain that area in vicinity ofpropeller is clear and that no person is standing nearby. As a precautionarymeasure, it is recommended that the propeller be removed.

CAUTIONDO NOT run engine above 1500 rpm, as suction created by seawater pickup pumpmay collapse water supply hose and cause engine to overheat.

WARNINGBe sure that engine compartment is well ventilated and that no gasoline vapors arepresent to prevent the possibility of a FIRE or EXPLOSION.

WARNINGDO NOT leave helm unattended while performing idle speed adjustment.

Used Spark Plug Analysis

Use the following illustrations for determining serviceability of spark plug. Spark plugcondition also can suggest a variety of possible engine malfunctions and, therefore, canindicate needed engine repairs. When old plugs are replaced, replace entire set. Performplug service only on those plugs suitable for additional service, using the followingprocedures:

1. Remove any oil deposits with solvent and dry plugs thoroughly.

2. Open electrode gap wide enough to permit cleaning and filing.

3. Remove combustion deposits from firing end of spark plug with a plug cleaner. Blow offwith compressed air to remove abrasives.

4. File electrode surfaces to restore clean, sharp edges. Again remove filings with com-pressed air.

5. Reset gap to specifications by bending only side electrode with proper tool.

IMPORTANT: When working on engine, spark plug holes and carburetor throatshould be kept covered to prevent foreign objects from entering combustionchamber.


Page 1C-4 90-861329--1 MARCH 1999

Spark Plug Analysis

Normal ConditionFew deposits are present and probably will be light tan or gray in color. This plug shows thatplug heat range is compatible with engine, and engine is electrically and mechanically ingood running condition. With proper plug servicing (clean, file and re-gap), this plug can bereinstalled with good results.

72420

Chipped InsulatorChipped insulator usually results from careless plug re-gapping. Under certain conditions,severe detonation also can split insulator firing ends. Plug must be replaced.

72420

Wet Fouling (Oil Deposits)Plug becomes shorted by excessive oil entering combustion chamber, usually in engine withmany hours of operation. Worn piston rings, cylinder walls, valve guides or valve stem sealsare causes of oil entering combustion chamber. Only engine repairs will permanently relieveoil wet fouling.

IMPORTANT: New engines or recently overhauled engines may wet foul plugs beforenormal oil control is achieved with proper break-in procedures. Such fouled plugsmay be serviced (clean, file and re-gap) and reinstalled.

72420


90-861329--1 MARCH 1999 Page 1C-5

Cold FoulingDry, black deposits indicate rich fuel mixture or weak ignition. Clogged flame arrestor,flooding carburetor, sticky choke or weak ignition components all are probable causes. If,however, only one or two plugs in set are fouled, check for sticking valves or bad ignitionleads. After correcting cause, service (clean, file and re-gap) plugs and reinstall.

72421

OverheatingInsulator is dull white or gray and appears blistered. Electrodes are eroded and there is anabsence of deposits. Check that correct plug heat range is being used. Also check forover-advanced ignition timing, cooling system malfunction, lean fuel/air mixtures, leakingintake manifold or sticking valves. Replace spark plugs.

72421

High Speed GlazingInsulator has yellowish, varnish-like color, indicating that temperatures suddenly have risen,usually during hard, fast acceleration under heavy load. Normal deposits do not get achance to blow off. Instead, they melt and form a conductive coating. Replace plugs. Ifcondition recurs, use colder heat range plug and service plugs more frequently.

72421


Page 1C-6 90-861329--1 MARCH 1999

Scavenger DepositsPowdery white or yellow deposits are built up on shell, insulator and electrodes. This isnormal appearance with certain branded fuels. Accumulation on ground electrodes andshell areas may be unusually heavy, but may be easily chipped off. Plugs can be serviced(clean, file and re-gap) and reinstalled.

72422

Pre-Ignition DamagePre-ignition damage is caused by excessive high temperatures. Center electrode meltsfirst, followed by ground electrode. Normally, insulators are white but may be dirty if plug hasbeen misfiring. Check for correct plug heat range, advanced ignition timing, lean fuelmixture, incorrect fuel used, malfunctioning cooling system, leaking intake manifold or lackof lubrication.

72422

Reversed Coil PolarityConcave erosion of ground electrode is an indication of reversed polarity. Center electrodewill show only normal wear. Engine will misfire and idle rough. To correct, reverse primarycoil leads. Replace spark plugs.

72422


90-861329--1 MARCH 1999 Page 1C-7

Splashed DepositsSpotted deposits, which sometimes occur after long delayed tune-up, accumulate after along period of misfiring. When normal combustion temperatures are restored, upon installa-tion of new plugs, deposits loosen from top of piston and head and are thrown against hotinsulator. Clean and service plugs and reinstall.

72423

Mechanical DamageMechanical damage to spark plug firing end is caused by foreign object in combustionchamber. Because of valve overlap, small objects can travel from one cylinder to another.Check all cylinders, intake manifold and exhaust material to prevent further damage.

72423


Page 1C-8 90-861329--1 MARCH 1999

Poor Boat Performance and/or Poor Maneuverability

Symptom Cause

A. Improper drive unit trim angle

B. Improper weight distribution

C. Boat is underpowered

Bow too lowD. Permanent or power hook in boatbottom

E. False bottom full of water

F. Improperly adjusted trim tabs (afterplanes)

G. Dirty boat bottom (marine growth)

A. Improper drive unit trim angle

B. Propeller pitch too great

C. Dirty boat bottom (marine growth)

D. Poor running engineBow too high E. Improper weight distribution

F. Rocker in boat bottom

G. False bottom full of water

H. Improperly adjusted trim tabs (afterplanes)

A. Drive unit installed too high on transom

B. Dirty or rough boat bottom

C. Damaged propeller; pitch too small; di-ameter too small

Propeller ventilatingD. Keel located too close to propeller ortoo deep in the water

E. Water pickup or through hull fittings lo-cated too close to propeller

F. Hook in boat bottom

G. Propeller plugged up with weeds


90-861329--1 MARCH 1999 Page 1C-9

Improper Full Throttle Engine RPM

RPM Too High

Cause Special Information

Propeller Damaged; pitch too low; diameter toosmall; propeller hub slipping.

Boat

Water pickup or through hull fittingsmounted too close to propeller(ventilation); keel located too close topropeller and/or too deep in the water(ventilation). Drive installed too high ontransom; wrong gear ratio.

Operation Unit trimmed out too far.

Engine coupler slipping

RPM Too Low


Propeller Damaged; pitch too great; diameter toogreat.

Boat

Dirty or damaged bottom; permanent orpower hook in bottom; false bottom full ofwater. Drive installed too low on transom;wrong gear ratio.

Operation Unit trimmed in too far.


Page 1C-10 90-861329--1 MARCH 1999

Engine Cranks Over But Will Not Start Or Is Hard To Start

Important Information1. First, determine which engine system is causing the problem. To make an engine run,

basic components fuel, spark (ignition), and compression are required. If all threecomponents are present, the engine should run. If any one of the three are missing,weak, or arriving at the wrong time the engine will not run.

2. Determine if there is fuel present by looking down the carburetor venturi while actuatingthrottle. There should be a stream of fuel coming out of the accelerator pump nozzlesif the carburetor has fuel.

3. Check ignition system operation. Remove coil wire from tower on distributor cap. Holdcoil wire near ground and check for spark while cranking engine over. Repeat procedurewith spark plug wires. If there is spark at the spark plug wires, remove the spark plugsand make sure they are correct type and heat range, and not fouled or burned.

4. Run a compression check on engine to make sure the engine is mechanically sound.

B R E

PN

BRE

BRE

+ C

+ C

PNK

PU

R

GRY

BRN

WHT

WHT

WH

T/G

RN

(+) (“C”)

PUR GRY

A

B

A

B

71572

a

b

cd

e

fg

i h

a - Ignition Coil Connectorb - Pick-Up Coilc - Distributor 3 Terminal Connectord - Distributor HEI Modulee - Filterf - Ignition Coilg - To Distributor Caph - Primaryi - Secondary


90-861329--1 MARCH 1999 Page 1C-11

EST Ignition System Check

Test DescriptionNumbers below refer to circled numbers on the diagnostic chart.

1. Two wires are checked, to ensure that an open is not present in a spark plug wire.

a. If spark occurs with EST connector disconnected, pick-up coil output is too low forEST operation.

2. A spark indicates the problem must be the distributor cap or rotor.

3. Normally, there should be battery voltage at the “C” and “+” terminals. Low voltage wouldindicate an open or a high resistance circuit from the distributor to the coil or ignitionswitch. If “C” terminal voltage was low, but “+” terminal voltage is 10 volts or more, circuitfrom “C” terminal to ignition coil or ignition coil primary winding is open.

4. Checks for a shorted module or grounded circuit from the ignition coil to the module. Thedistributor module should be turned “OFF,” so normal voltage should be about 12 volts.If the module is turned “ON,” the voltage would be low, but above 1 volt. This could causethe ignition coil to fail from excessive heat. With an open ignition coil primary winding,a small amount of voltage will leak through the module from the “BAT” to the “TACH”terminal.

5. Applying a voltage (1.5 to 8 volts) to module terminal “P” should turn the module “ON”and the “tach” terminal voltage should drop to about 7-9 volts. This test will determinewhether the module or coil is faulty or if the pick-up coil is not generating the propersignal to turn the module “ON.” This test can be performed by using a DC battery witha rating of 1.5 to 8 volts. The use of the test light is mainly to allow the “P” terminal tobe probed more easily. Some digital multi-meters can also be used to trigger the moduleby selecting ohms, usually the diode position. In this position the meter may have avoltage across its terminals which can be used to trigger the module. The voltage in theohm’s position can be checked by using a second meter or by checking themanufacturer’s specification of the tool being used.

6. This should turn “OFF” the module and cause a spark. If no spark occurs, the fault ismost likely in the ignition coil because most module problems would have been foundbefore this point in the procedure. A module tester could determine which is at fault.


Page 1C-12 90-861329--1 MARCH 1999

Ignition System Check(1 of 2)

SPARK

CHECK FUEL, SPARK PLUGS, ETC.SEE “TROUBLESHOOTING.”

�

• DISCONNECT 4 TERMINAL CONNECTOR ON DISTRIBUTOR AND CHECK FOR SPARK.

• IF A TACHOMETER IS CONNECTED TO THE TACH TERMINAL, DISCONNECT ITBEFORE PROCEEDING WITH THE TEST.

• CHECK SPARK AT PLUG WIRE USING AN INDUCTIVE PICKUP TIMING LIGHT WHILE CRANKING. A FLASHING LIGHT INDICATES SPARK. (IF NO SPARK ON FIRST WIRE, CHECK SECOND WIRE.) A FEW SPARKS AND THEN NOTHINGIS CONSIDERED NO SPARK.

NO SPARK

• CHECK FOR SPARK AT COIL WIRE WITH TIMING LIGHT WHILE CRANKING. (LEAVE TIMING LIGHT CONNECTED TO COIL WIRE FOR STEPS 3-6).

NO SPARK

• DISCONNECT DISTRIBUTOR 2 TERMINAL “C/+” CONNECTOR.

• IGNITION SWITCH “ON,” ENGINE STOPPED.• CHECK VOLTS AT “+” AND “C” TERMINALS OF DISTRIBUTOR HARNESS CONNECTION.

��

�

�

• RECONNECT DISTRIBUTOR 2TERMINAL CONNECTOR.

• WITH IGNITION “ON,” CHECK VOLTAGE FROM TACH. TERMINAL TO GROUND

BOTH TERMINALS 10 VOLTS OR MORE

CHECK FOR OPEN ORGROUND IN CKT. FROM“C” TERMINAL TO IGNI-TION COIL. IF CKT IS OK,FAULT IS IGNITION COILOR CONNECTION.

UNDER 10 VOLTS“C”TERMINAL ONLY�

REPAIR OPENTACH. LEAD ORCONNECTION ANDREPEAT TEST #4.

• CONNECT TEST LIGHT FROM TACH. TERMINAL TO GROUND.

• CRANK ENGINE AND OBSERVE LIGHT.

OVER 10 VOLTS

REPLACE MODULE ANDCHECK FOR SPARKFROM COIL AS IN STEP 6.

UNDER 1 VOLT 1 TO 10 VOLTS

REPLACEIGNITIONCOIL.

NOSPARK

SPARK

SYSTEMOK

NO SPARK SPARK

REPAIR WIRE FROM MOD-ULE “+” TERMINAL TO “B”TERMINAL OF BLACKIGNITION COIL CONNEC-TOR OR PRIMARY CKT. TOIGNITION SWITCH.

BOTH TERMINALSUNDER 10 VOLTS

CHART CONTINUED ON NEXT PAGEa b

INSPECT CAP FOR WATER,CRACKS, ETC. IF OK,REPLACE ROTOR.

SPARK

REPLACE MAGNETICSHAFT ASSEMBLY.


90-861329--1 MARCH 1999 Page 1C-13

Ignition System Check (2 of 2)

� REPLACE IGNITION COIL AND RECHECK FOR SPARK WITH TIMING LIGHT. IF STILL NOSPARK, REINSTALL ORIGINALCOIL AND REPLACE DISTRIBUTOR MODULE.

LIGHT ONSTEADY

LIGHTBLINKS

NO DROP IN VOLTAGE

CHECK MODULE GROUND.IF OK, REPLACE MODULE.

• CHECK FOR SPARK FROM COIL WIRE WITH TIMING LIGHT AS TEST LIGHT IS REMOVED FROM MODULE TERMINAL

VOLTAGE DROPS

�

SPARK

• REPLACE IGNITION COILAND REPEAT STEP 5.

NO SPARK

• IS ROTATING POLE PIECE STILL MAGNETIZED?

SYSTEM OKIGNITION COIL REMOVED IS OK,REINSTALL COIL AND CHECKCOIL WIRE FROM DIST. CAP. IFOK, REPLACE DISTRIBUTORMODULE.

REPLACE POLEPIECE ANDSHAFT ASSEMBLY.

NOYES

CHECK PICK-UP COIL ORCONNECTIONS (COILRESISTANCE SHOULD BE500-1500 OHMS ANDNOT GROUNDED.)

Fig. 1

TEST LIGHT

TO DCPOWERSUPPLY(1.5 to 8 V)

ba

NO SPARK SPARK

CHART CONTINUEDFROM PREVIOUSPAGE

• DISCONNECT DISTRIBUTOR 4 TERMINAL CONNECTOR.• REMOVE DISTRIBUTOR CAP.• DISCONNECT PICK-UP COIL CONNECTOR FROM MODULE.• CONNECT VOLTMETER FROM TACH. TERMINAL TO GROUND.• IGNITION “ON.”• INSULATE A TEST LIGHT PROBE TO 1/4, FROM TIP AND

NOTE VOLTAGE, AS TEST LIGHT IS MOMENTARILY CON-NECTED FROM A VOLTAGE SOURCE (1.5 TO 8 V) TO MODULE TERMINAL “P” (CHART 1 OF 2 PAGE 11).


Page 1C-14 90-861329--1 MARCH 1999

Engine Will Not Crank Over/Starter Inoperative


Remote control lever not in neutralposition

Battery charge low; damaged wiring; looseelectrical connections

Circuit breaker tripped

Blown fuse

Ignition switch

Slave solenoid

Faulty neutral start safety switch Open circuit

Starter solenoid

Starter motor

Mechanical engine malfunction

Charging System Inoperative


Loose or broken drive belt

Engine rpm too low on initial start Rev engine to 1500 rpm

Loose or corroded electrical connections

Faulty battery gauge Best way to test is to replace gauge

Battery will not accept charge Low electrolyte or failed battery

Faulty alternator or regulator

Refer to SECTION 4C for complete“Charging System” diagnosis procedures


90-861329--1 MARCH 1999 Page 1C-15

Noisy Alternator


Loose mounting bolts

Drive belt Worn, frayed or loose belt

Loose drive pulley

Worn or dirty bearings

Faulty diode trio or stator

Fuel System Rich


Warm engine carburetor percolation Fuel boils out of float bowl when shut offand warm. Floods intake manifold.

Clogged flame arrestor

Automatic choke not opening

Float adjustment

Float leaks or is saturated with fuel

Needle and seat leaking

Carburetor gaskets leaking

Excessive fuel pump pressure Unseats needle and seat

Cracked or porous carburetor body


Page 1C-16 90-861329--1 MARCH 1999

Fuel System Lean


Empty fuel tank

Fuel shut-off valve closed (if equipped)

Vapor lock Engine will not start after warm engineshut down

Automatic choke Stuck open, wrong adjustment

Fuel tank vent plugged

Engine will start initially. After a short timeof running, engine will stall and will notrestart for a period of time. Can verify it isa vent problem by running engine withfiller cap loose. Fill cap will act as a vent.

Air leak on suction side of fuel system Sucks air into fuel system reducing fuelvolume

Plugged or pinched fuel line

Fuel pump Low pump pressure

Carburetor Malfunction

Symptoms Cause

A. Needle and seat

B. Float adjustment

C. Saturated float

Flooding D. Gaskets leaking

E. Cracked fuel bowl

F. Fuel percolation

G. Automatic choke

A. Idle rpm too low

B. Idle mixture screws

C. Idle passages dirty

Rough idle D. Throttle valves not closing

E. Engine flooding

F. Vacuum leak

G. Throttle body heat passages plugged


90-861329--1 MARCH 1999 Page 1C-17

Carburetor Malfunction (continued)

A. Accelerator pump

B. Leaking gaskets

C. Automatic choke

D. Power piston or power valve

Hesitation or acceleration flatness E. Throttle valves

F. Throttle body heat passages plugged

G. Main metering jets

H. Float adjustment

I. Secondary air valve wind-up

A. Main metering jets

B. Leaking gaskets

C. Float adjustmentEngine surges

D. Saturated float

E. Power piston or valve

F. Throttle valves

A. Power piston or valve

B. Float adjustmentLow top speed or lack of power

C. Main metering jets

D. Leaking gaskets

A. Idle rpm too low


Poor cold engine operation C. Throttle valves

D. Automatic choke

E. Engine flooding

A. Idle rpm too low


C. Engine flooding

Engine stalls D. Automatic choke

E. Dirt in carburetor

F. Accelerator pump

G. Leaking gaskets

Hard starting Refer to “Engine Starts Hard”


Page 1C-18 90-861329--1 MARCH 1999

Engine Runs Poorly At Idle



Improper idle fuel mixture adjustment

Problem in ignition system causing theengine to run rough

Idle mixture screw adjusted incorrectly

Engine floods at idle Bad needle and seatEngine floods at idleIncorrect float level drop

If carburetor (2 barrel only) has a solidneedle, replace with a spring loadedneedle

Moisture on ignition components Cap or spark plug wires arcing

Water in fuel

Low grade or stale fuel

Incorrect ignition timing

Automatic choke

Spark plugs Fouled, burned, cracked porcelain

Spark plug wires Insulation breakdown, wires broken

Defective coil

Cracked or dirty distributor cap

Incorrect float level

Dirty carburetor

Vacuum leak Leak at manifold or carburetor base

Incorrect fuel pump pressureToo low - can’t supply the carburetor

Too high - unseats the needle and seat

Low compression Also check for blown head gasket

Loose or worn distributor Timing changes

Water leaking into cylinders Head gasket, exhaust manifold, crackedhead or valve seat

Loose or broken engine mounts


90-861329--1 MARCH 1999 Page 1C-19

Engine Acceleration Is Poor


Also refer to “Poor Boat Performance”

Idle mixture screws

Incorrect ignition timing

Incorrect distributor or amplifier advancecurve

Refer to SECTION 4B

Accelerator pumpCheck for stream of raw fuel fromaccelerator pump discharge nozzle, whenopening throttle with engine shut off

Cracked or dirty distributor cap or rotor

Vacuum leak Intake manifold or carburetor base

Spark plugs Fouled, burned; wrong heat range;cracked porcelain

Float adjustment

Dirty carburetor

Low compression

Engine Runs Poorly At High RPM


Also refer to “Poor Boat Performance”

Crankcase overfilled with oil Check oil level with boat at rest in thewater.

Anti-siphon valve (if equipped) Restricting fuel supply

Plugged fuel tank vent

Fuel supply Refer to “Carburetor Malfunctions”(See “Table of Contents”)

Ignition timing

Low grade of fuel or water in the fuel

Spark plugs Fouled, burned, cracked porcelain,incorrect heat range

Spark plug wires Poor insulation, broken wires

Distributor cap or rotor Dirty or cracked


Page 1C-20 90-861329--1 MARCH 1999

Engine Runs Poorly At High RPM (continued)


Coil

Distributor Excessive play in shaft

Engine overheating Refer to “Engine Overheats”

Low compression Worn valves, rings, cylinders, etc.

Restricted exhaust

Poor Fuel Economy


Fuel leaks

Operator habits

Prolonged idling; slow acceleration; failureto cut back on throttle once boat is onplane; boat overloaded; uneven weightdistribution

Engine laboringBent, damaged or wrong propeller. Watertest boat for proper operating rpm at wideopen throttle


Engine compartment sealed too tight Not enough air for engine to run properly

Boat bottom Dirty (marine growth), hook, rocker

Carburetor

Idle mixture settings, accelerator pumpadjustments, linkage binding, chokeadjustment, carburetor flooding over, mainfuel jets

Improper fuel

Crankcase ventilation system not working

Engine needs tune-up

Engine running too cold or too hot

Plugged or restricted exhaust

Engine Low compression


90-861329--1 MARCH 1999 Page 1C-21

Radio Noise


A popping noise that will increase withengine rpm. Noise will stop as soon asengine is turned off.

Ignition System - wrong spark plugs;cracked distributor cap; cracked coil tower;leaking spark plug wires; moisture onignition components

High pitched whine in the radio Alternator - poor brush contact on the sliprings

A hissing or crackling noise wheninstruments are jarred with ignition on

Instrumentation - loose connections orantennae wire routed too close toinstruments

Varying unexplained noises

Accessories - bilge pump, bilge blower;fish finder; depth locator; cabin heatermotor, etc. Disconnect one at a time untilnoise disappears.

Troubleshooting With Vacuum Gauge

Reading Cause

Steady reading between 15-21 inches atidle rpm

Normal

Extremely low reading, but steady at idlerpm

Vacuum leak; incorrect timing;underpowered boat; faulty boat bottom

Fluctuates between high and low at idlerpm

Blown head gasket between two adjacentcylinders

Fluctuates 4 or 5 inches very slowly at idlerpm

Carburetor needs adjustment; spark pluggap too narrow; valves are sticking

Fluctuates rapidly at idle, steadies as rpmis increased

Valve guides are worn

Continuously fluctuates between low andnormal reading at regular intervals at idlerpm

Burned or leaking valve

Miscellaneous


Low grade or stale fuel

Water in fuel


Page 1C-22 90-861329--1 MARCH 1999

Instrumentation Malfunction


Faulty wiring, loose or corroded terminals

Faulty key switch Test, as outlined in SECTION 4D

Faulty gauge Test, as outlined in SECTION 4D

Faulty sender Test, As outlined in SECTION 4D

Engine Noise

Important InformationNo definite rule or test will positively determine source of engine noise. Use the followinginformation only as a general guide to engine noise diagnosis.

1. Use a timing light to determine if noise is timed with engine speed or one-half enginespeed. Noises timed with engine speed are related to crankshaft, rods, pistons, pistonpins and flywheel. Noises timed to one-half engine speed are valve train related.

2. The use of a stethoscope can aid in locating a noise source. Because noise will travelto other metal parts not involved in the problem, caution must be exercised.

3. If you believe noise is confined to one particular cylinder, ground spark plug leads oneat a time. If noise lessens noticeably or disappears, it is isolated to that particular cylin-der.

4. Try to isolate the noise to location in engine: front to back, top to bottom. This can helpdetermine what components are at fault.

5. Sometimes noises can be caused by moving parts coming in contact with other compo-nents. Examples are: flywheel or coupler; exhaust flappers rattling against exhaust pipe;crankshaft striking (pan, pan baffle, or dipstick tube); rocker arm striking valve cover;and loose flywheel cover. In many cases if this is found to be the problem, a completeengine teardown is not necessary.

6. When noise is isolated to a certain area and component, removal and inspection will berequired. Refer to proper sections of service manual for information required for service.

7. If noise cannot be distinguished between engine and drive unit, remove drive from boat.Run a water supply directly to engine. Run engine without the drive to determine if noiseis still there.


90-861329--1 MARCH 1999 Page 1C-23

Valve Cover Area

Location Possible Causes

A. Rocker arm striking valve cover

Valve cover area, timed to one-half engine B. Rocker arm out of adjustmentspeed, noise could be confined to one C. Worn rocker armcylinder or may be found in any multitudeof cylinders D. Bent push rod

E. Collapsed filter

Cylinder Area


A. Sticking valve

B. Carbon build-up

C. Connecting rod installed wrong

Cylinder area, may be confined to one D. Bent connecting rodcylinder or found in more than onecylinder, timed to engine speed E. Pistoncylinder, timed to engine speed

F. Piston rings

G. Piston pin

H. Cylinder worn

Camshaft Area


A. Crankshaft timing sprocket

B. Timing chainCamshaft area, front of engine, C. Fuel Pumptimed to one half engine speed

D. Valve Lifter

E. Cam Bearings

A. Fuel PumpCamshaft area, center ofengine, timed to one half B. Valve Lifterengine speed C. Cam bearing

A. Distributor gearCamshaft area, rear of engine, B. Valve liftertimed to one half engine speed

C. Cam bearings

A. Loss of oil pressureCamshaft area, throughoutengine, timed to one half B. Valve liftersengine speed C. Cam bearings


Page 1C-24 90-861329--1 MARCH 1999

Crankshaft Area


A. Crankshaft timing sprocket

Crankshaft area, front of engine, timed to B. Timing chainCrankshaft area, front of engine, timed toengine speed C. Main bearing

D. Rod bearing

A. Crankshaft striking pan or pan baffleCrankshaft area, center of engine, timed B. Main bearingto engine speed

C. Rod bearing

A. Loose flywheel cover

B. Loose couplerCrankshaft area, rear of engine, timed to C. Loose flywheelengine speed

D. Main bearing

E. Rod bearing

A. Loss of oil pressureCrankshaft area, throughout engine, timed B. Main bearingsto engine speed

C. Rod bearings


90-861329--1 MARCH 1999 Page 1C-25

Miscellaneous

Location / Noise Possible Causes

A. Advanced timing

B. Low octane fuelEngine spark knock

C. Engine running hot

D. Carbon deposits in engine

A. Wrong ignition timing

B. Carburetor set too lean

C. Faulty accelerator pump

Popping through carburetor D. Vacuum leak

E. Valve adjustment

F. Valve timing

G. Burned or stuck valve

A. Vacuum leak

B. Leaking exhaust (manifolds or pipes)Hissing

C. Loose cylinder heads

D. Blown head gasket

A. Vacuum leakWhistle

B. Dry or tight bearing in an accessory

A. Leaking high tension lead

Sparks jumping B. Cracked coil tower

C. Cracked distributor cap

A. Drive belt slipping

Squeaks or squeals B. Dry or tight bearing in an accessory

C. Parts rubbing together

Rattling in exhaust pipe area A. Exhaust shutters


Page 1C-26 90-861329--1 MARCH 1999

Oil Pressure

Miscellaneous

Problem Special Information

Measuring oil pressureUse a good automotive oil pressure testgauge. Do not rely on the oil pressuregauge in the boat.

Check engine oil level with boat at rest inthe water

Oil level should be between the ADD andFULL marks

Oil level in crankcase above FULL mark

May cause loss of engine rpm, oilpressure gauge fluctuation, drop in oilpressure, and hydraulic valve lifter noiseat high rpm

Oil level in crankcase below ADD markLow oil pressure; oil pressure gaugefluctuation; internal engine noise and/ordamage

Change in oil pressure

This may be a normal condition. Oilpressure may read high in the cooler timesof the day, and when engine is not up tooperating temperature. As the airtemperature warms up and engine isrunning at normal opening temperature, itis normal for oil pressure to drop.

Low engine oil pressure at idle

With modern engines and engine oils, lowoil pressure readings at idle do notnecessarily mean there is a problem. Ifvalve lifters do not “clatter” (at idle), thereis a sufficient volume of oil to lubricate allinternal moving parts properly. The reasonfor the drop in oil pressure is that engineheat causes an expansion of the internaltolerances in the engine and, also, the oilwill thin out somewhat from heat.

Low engine oil pressure at idle afterrunning at a high rpm

Refer to preceding items

Boats with dual engines

It is not uncommon to see different oilpressure readings between the twoengines, as long as both engines fallwithin specifications. Differences in oilpressure can be attributed to differencesin engine tolerances, gauges, wiring,senders, etc.

Boats with dual stations Refer to preceding


90-861329--1 MARCH 1999 Page 1C-27

Low Oil Pressure


Low oil level in crankcase

Defective oil pressure gauge and/orsender

Verify with an automotive test gauge.Refer to SECTION 4D for instrumenttesting.

Thin or diluted oil

Oil broken down; contains water or gas;wrong viscosity; engine running too hot ortoo cold; excessive idling in cold water(condensation)

Oil pump

Relief valve stuck open; pickup tuberestricted; worn parts in oil pump; air leakon suction side of oil pump or pickup oiltube

Oil leak can be internal or external Oil passage plugs leaking, cracked orporous cylinder block

Excessive bearing clearance Cam bearings, main bearings, rodbearings

High Oil Pressure


Oil too thick Wrong viscosity, oil full of sludge or tar

Defective oil pressure gauge and/orsender

Verify with an automotive test gauge

Clogged or restricted oil passage

Oil pump relief valve stuck closed


Page 1C-28 90-861329--1 MARCH 1999

Excessive Oil ConsumptionNOTE: Normal consumption is one quart of oil consumed in 5-15 hours of operation at wide-open-throttle (especially in a new or rebuilt engine).


Oil leaks Clean bilge, run engine with clean whitepaper on bilge floor, locate oil leak(s)

Oil too thin Oil diluted or wrong viscosity

Oil level too high

Drain holes in cylinder head plugged Oil will flood valve guides

Defective valve seals

Intake manifold gasket leaking

Worn valve stems or valve guides

Defective oil cooler (if so equipped) Crack in cooler tubes

Defective piston ringsGlazed, scuffed, worn, stuck, improperlyinstalled; ring grooves worn; improperbreak-in; wrong end gap

Defective cylindersOut of round, scored, tapered, glazed;excessive piston to cylinder clearance;cracked piston

Excessive bearing clearance


90-861329--1 MARCH 1999 Page 1C-29

Water in Engine

Important InformationIMPORTANT: First determine location of water in engine. This information can be ofgreat help when trying to determine where the water came from and how it got intothe engine. The three most common problems are “water on top of pistons, water incrankcase oil or water in crankcase oil and on top of pistons.”

The first step, after locating water, is to remove all the water from the engine by removingall spark plugs and pumping cylinders out by cranking engine over. Next change oil and filter.Now, start engine and see if problem can be duplicated. If problem can be duplicated, thereis probably a mechanical problem. If the problem cannot be duplicated, the problem is eitheran operator error or a problem that exists only under certain environmental conditions.

If water is contained to cylinder(s) only, it is usually entering through the intake system,exhaust system or head gasket.

If the water is contained to crankcase only, it is usually caused by a cracked or porous block,a flooded bilge or condensation.

If the water is located in both the cylinder(s) and the crankcase, it is usually caused by waterin the cylinders getting past the rings and valves or complete submersion.

Check for rust in the intake manifold or exhaust manifolds. Rust in these areas will show thatif the water entered these areas.

If water is contained to cylinder(s) only, it is usually entering through the intake system,exhaust system or head gasket.

Water In Crankcase


Water in boat bilgeBoat has been submerged or bilge waterwas high enough to run in through dipsticktube

Water seeping past piston rings or valves Refer to “Water in Engine” (“On Top ofPistons”)

Engine running cold Defective thermostat, missing thermostat;prolonged idling in cold water

Intake manifold leaking near a waterpassage

Cracked or porous casting Check cylinder head, cylinder block, andintake manifold


Page 1C-30 90-861329--1 MARCH 1999

Water On Top Of Pistons


Operator shut engine off at high rpm

Engine “diesels” or tries to run backwards Engine out of tune, poor fuel, high idlerpm, timing set too high

Rain water running into flame arrestor Hatch cover

Spark plug misfiring Improper combustion causes moisture inthe air to accumulate in the cylinder

Backwash through the exhaust system

Improper engine or exhaust hoseinstallation

Cracked exhaust manifold

Improper manifold to elbow gasketinstallation

Loose cylinder head bolts

Blown cylinder head gasket Check for warped cylinder head orcylinder block

Cracked valve seat

Porous or cracked casting Check cylinder heads, cylinder block, andintake manifold


90-861329--1 MARCH 1999 Page 1C-31

Engine Overheats

Mechanical


Engine rpm below specifications atwide-open-throttle (engine laboring)

Damaged or wrong propeller; growth onboat bottom; false bottom full of water

Wrong ignition timing Timing too far advanced or retarded

Sticking distributor advance weights

Spark plug wires crossed (wrong firingorder)

Lean fuel mixture Refer to “Carburetor Malfunction” in thissection

Wrong heat range spark plugs

Exhaust restriction

Valve timing off Jumped or improperly installed timingchain

Blown head gasket(s)

A blown head gasket(s) normally cannotbe detected by a compression check.Normally the engine will run at normaltemperature at low rpm, but will overheatat speeds above 3000 rpm.

Engines that are seawater cooled:Using a clear plastic hose, look for airbubbles between seawater pump andengine. If there are no bubbles present,install clear plastic hose betweenthermostat housing and manifold(s). If airbubbles are present at a higher rpm, it is agood indication there is a blown headgasket.

Insufficient lubrication to moving parts ofengine

Defective oil pump, plugged oil passage,low oil level


Page 1C-32 90-861329--1 MARCH 1999

Cooling System


IMPORTANT: The first step is to verify ifthe engine is actually overheating or thetemperature gauge or sender is faulty

IMPORTANT: Best way to test gauge orsender is to replace them.

Loose or broken drive belt

Seawater shutoff valve partially or fullyclosed (if equipped)

Clogged or improperly installed seastrainer

Loose hose connections betweenseawater pickup and seawater pump inlet(models with belt driven seawater pumponly)

Pump will suck air. Pump may fail to primeor will force air bubbles into coolingsystem.

Seawater inlet hose kinked or collapsed

Seawater pickup clogged

Obstruction on boat bottom causing waterturbulence

Obstruction will be in front of seawaterpickup, causing air bubbles to be forcedinto cooling system

Defective thermostat

Exhaust elbow water outlet holes plugged

Insufficient seawater pump operation Worn pump impeller

Obstruction in cooling system such ascasting flash, sand, rust, salt, etc.

Refer to water flow diagram for enginetype being serviced

Engine circulating pump defective

Also refer to “Engine Overheats(Mechanical)”

IMPORTANT: In addition to previouschecks, make the following checks ifengine is equipped with closedcooling.

Low coolant level

Antifreeze not mixed properlyAntifreeze should be mixed 50/50 ormaximum 60/40 (60% antifreeze, 40%water)

Heat exchanger cores plugged

Water hoses reversed at the waterdistribution block

Refer to water flow diagram in SECTION 6


90-861329--1 MARCH 1999 Page 1C-33

Power Steering

Poor, Erratic or No Assist


Drive belt Worn, broken or out of adjustment

Low fluid level

Air in systemAir leak in lines or pump, or air frominstallation. Refer to SECTION 8A forbleeding procedure.

Leaking hoses Refer to SECTION 8A for bleedingprocedure.

Steering cables and/or steering helmCable or helm partially frozen from rust orcorrosion; cable over-lubricated; impropercable installation

Binding in sterndrive unit Refer to appropriate Sterndrive ServiceManual

Restriction in hydraulic hoses Causes loss of pressure

Control valve not positioned properly, notbalanced properly, or the mounting nut isloose

Mounting bracket adjusting screw loose ormounting tube is loose

Faulty pump Flow control valve may be sticking

Worn piston ring or scored housing bore incylinder

Causes loss of pressure

Leaking valve body or loose fitting spool


Page 1C-34 90-861329--1 MARCH 1999

Noisy Pump


Drive belt Check belt tension

Low fluid level

Air in fluid Air leak in lines, pump, or air forminstallation

Faulty pump Use stethoscope to listen for noise inpump

Restricted fluid passages Kinks or debris in hoses or debris inpassages

Stop nut adjusted improperly Refer to appropriate Sterndrive ServiceManual

Steering cables installed that do not meetBIA standards

Refer to appropriate Sterndrive ServiceManual

Fluid Leaks


Loose hose connections Refer to SECTION 8A for bleeding instruc-tions

Damaged hose

Oil leaking from top of pump System overfilled; fluid contains water;fluid contains air

Cylinder piston rod seal

Faulty seals in valve

Faulty seals in O-rings in pump

Cracked or porous metal parts


90-861329--1 MARCH 1999 Page 1C-35

Insufficient Water Flow From Alpha One Sterndrive UnitSeawater Pickup Pump


Seawater shutoff valve partially or fullyclosed (if equipped)

Water pickup clogged with foreign material

Kinked or broken bell housing to gimbalhousing water tube hose

Corroded through gimbal housing watertube

Water pickup inserts warped. (Engine willoverheat while boat is underway.)

Water pickup must not protrude abovegear housing surface or inserts will createan irregular or turbulent water flow overthe water pickup holes. Consequently, thismay cause loss of cooling water andsubsequent engine overheating. Thiscondition can be identified by cavitationburn (pitting or erosion) on the gearhousing in the area aft of the water pickup.

Damaged gear housing or accessoriesimproperly installed on boat bottom ortransom (speedometer pick up, depthsounder transducer, etc.) Substantialamount of barnacles or other marinegrowth on gear housing or boat bottom.(Engine will overheat while underway only)

An object or an irregularity on boat or gearhousing in area close to to water pickupscould create turbulence in water flowgoing to water pickups. This could aeratethe water flow and cause engine tooverheat

Sterndrive installed too high on transom ordrive unit trimmed out too far out allowingair to be drawn into pump. (Engine willoverheat while underway only)

Contact boat company if sterndrive is toohigh. Instruct operator on proper trimmingtechnique if unit is trimmed out too far.

Bell housing-to-driveshaft housing O-ringmissing or damaged

Faulty seawater pickup pump

Seawater pickup tube corroded through

Driveshaft housing water pocket covercracked

Broken impeller blade or other obstructionin water passages (usually lodges in drive-shaft housing water pocket cover or crossdrilled water passage).

To check cross drilled water passages indriveshaft housing, remove plug and pipeplug located under decal on starboard sideof housing. Drive unit must be shifted intoreverse to remove pipe plug.

Water passage in driveshaft housingimproperly drilled


Page 1C-36 90-861329--1 MARCH 1999


2A

MCM 3.0L (181 CID) - ALPHA DRIVESERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 2A-1

REMOVAL AND INSTALLATIONSection 2A - MCM 3.0L (181 cid) - Alpha Drive

Table of Contents

Torque Specifications 2A-2. . . . . . . . . . . . . . . . . . Lubricants/Sealers/Adhesives 2A-2. . . . . . . . . . . Tools 2A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 2A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Removal 2A-3. . . . . . . . . . . . . . . . . . . .

Installation 2A-8. . . . . . . . . . . . . . . . . . . . . . . . . . . Engine Installation 2A-8. . . . . . . . . . . . . . . . . . Engine Alignment 2A-11. . . . . . . . . . . . . . . . . . Engine Connections 2A-13. . . . . . . . . . . . . . .

MCM 3.0L (181 CID) - ALPHA DRIVE SERVICE MANUAL NUMBER 26

Page 2A-2 90-861329--1 MARCH 1999

Torque Specifications

DESCRIPTION lb-in. lb-ft Nm

Power Steering Hydraulic Hose Fittings 23 31

Front Engine Mounts 35 47

Rear Engine Mounts 38 52

Drive Unit Shift Cables (Cable End andCable End Guide)

Tighten Until Contacts, Then Loosen 1/2Turn. Spread Cotter Keys

Remote Control Shift Cables

Remote Control Throttle Cables

Hose ClampsTighten Securely

Battery Cables

Lubricants/Sealers/Adhesives

Description Part Number

Quicksilver Engine Coupler Spline Grease 92-816391A4

Quicksilver 2-4-C Marine Lubricant With Teflon 92-825407A3

Quicksilver Liquid Neoprene 92-25711--3

Loctite Pipe Sealant with Teflon Obtain Locally

Tools


Engine Alignment Tool 91-805475A1


90-861329--1 MARCH 1999 Page 2A-3

Removal

IMPORTANT: Sterndrive unit must be removed prior to engine removal. Refer toSterndrive Service Manual.

Engine Removal1. Disconnect battery cables from battery.

22052

a

b

c

a - Negative (-) Battery Cableb - Positive (+) Battery Cablec - Rubber Boot (Slid Back From Terminal)

2. Remove instrument harness connector plug from engine harness receptacle after loos-ening clamp.

WARNINGBe careful when working on fuel system. Gasoline is extremely flammable andhighly explosive under certain conditions. Do not smoke or allow spark or openflame in area. Wipe up any spilled fuel immediately.

3. Disconnect and plug fuel line to prevent fuel in tank from leaking into bilge.

50738b

a

a - Fuel Pumpb - Disconnect Fuel Inlet Line Here


Page 2A-4 90-861329--1 MARCH 1999

4. Disconnect throttle cable from carburetor and retain locknuts and hardware.

75810

a

bc

de

a - Cable End Guideb - Throttle Cable Anchor Screwc - Cable Barreld - Elastic Stop Nut And Flat Washere - Throttle Lever

5. Disconnect shift cables and shift assist assembly (if equipped).

75811

e

abc

d

a - Locking Nutb - Shift Cable Endc - Cotter Pind - Shift Assist Assemblye - Clevis Pin (w/Cotter Pin)


90-861329--1 MARCH 1999 Page 2A-5

6. Disconnect and cap power steering hoses. Plug control valve hose connection holes.

75812

b

a

a - Power Steering Hosesb - Control Valve

7. Loosen clamp and unplug wiring harness.

50626

a

b

c

a - Engine Wiring Harness Receptacle (Bracket)b - Instrumentation Wiring Harnessc - Hose Clamp

8. Disconnect bullet connectors of trim sender wires (coming from transom assembly) fromengine harness.

NOTE: After wires are disconnected, remove them from clamps or Sta-Straps retainingthem to engine or hoses.


Page 2A-6 90-861329--1 MARCH 1999

9. Disconnect engine harness wires from shift cut-out switch harness.

75499

a

a - Shift Cutout Switch Wires

10. Disconnect MerCathode wires from MerCathode controller if equipped.

11. Disconnect seawater inlet hose from gimbal housing.

72614

ba

c

a - Water Tubeb - Hose Clamp (Tighten Securely)c - Water Hose

12. Loosen hose clamps and disconnect exhaust elbow hose.

13. Remove both shift cables from shift plate. Retain locknuts and hardware.


90-861329--1 MARCH 1999 Page 2A-7

14. Disconnect any grounding wires and accessories that are connected to engine.

50636

a

a - Ground Stud

15. Disconnect (and suitably plug) fluid hoses from power steering control valve on transom.

CAUTIONCenter lifting eye (located on top of thermostat housing) is used for engine align-ment only. DO NOT use to lift entire engine.

CAUTIONDO NOT allow lifting sling to hook or compress engine components or damage willoccur.

16. Support engine with suitable sling through lifting eyes on engine and remove front andrear engine mounting bolts. Retain hardware.

75815

ab b

Typicala - Center Lifting (Aligning) Eyeb - Lifting Eye

17. Carefully remove engine. DO NOT hit power steering control valve.


Page 2A-8 90-861329--1 MARCH 1999

InstallationEngine Installation

1. Be certain fiber washers (cemented in place) on inner transom plate are present. Inspectfiber washers. Replace if worn or damaged.

2. Install double wound lockwashers onto inner transom plate inside fiber washer.

72023

a

d

cb

a - Double Wound Lockwasherb - Fiber Washerc - Inner Transom Plate Mountd - Locknut

3. Be certain rear engine mount locknuts are in position as shown.

4. Lubricate exhaust bellows with soap and water to ease installation.

5. Lubricate engine coupling splines with Quicksilver Engine Coupler Spline Grease.

72017b

a

a - Lubricate Splines With Quicksilver Engine Coupler Grease 92-816391A4b - Grease Fitting

CAUTIONCenter lifting eye (located on top of thermostat housing) is used for engine align-ment only. DO NOT use to lift entire engine.

CAUTIONDO NOT allow lifting sling to hook or compress engine components or damage willoccur.

6. Attach a suitable sling to lifting eyes on engine and adjust so that engine is level whensuspended.


90-861329--1 MARCH 1999 Page 2A-9

7. Lift engine into position (in boat), using an overhead hoist.

75815

ab b

a - Center Lifting (Aligning) Eyeb - Lifting Eye

8. Align rear engine mounts with inner transom plate mounts while simultaneously aligningexhaust tubes with exhaust pipe hoses (bellows). Do not fasten attaching hardware untilyou have aligned engine.

75819

b

c

a

a - Bellowsb - Clampsc - Exhaust Pipe


Page 2A-10 90-861329--1 MARCH 1999

IMPORTANT: Engine attaching hardware must be installed in sequence shown.

9. Install both rear engine mounting bolts and hardware as shown.

10. Torque mounting bolts to 38 lb-ft (52 Nm).

72535

a

bc

de

f

g

h

a - Rear Engine Mounting Boltb - Large Steel Washerc - Metal Spacerd - Rear Engine Mounte - Double Wound Lockwasherf - Fiber Washerg - Inner Transom Plate Mountsh - Locknut (Hidden In This View)

CAUTIONWhen lowering engine into position DO NOT set engine on shift cable. Shift cableouter casing can be crushed causing difficult or improper shifting.

11. Set engine down on stringers and relieve hoist tension. Disconnect sling from enginelifting eyes and switch sling to center lifting eye.

75815

ab b

a - Center Lifting (Aligning) Eyeb - Lifting Eyes (rear lifting eye hidden in this view)


90-861329--1 MARCH 1999 Page 2A-11

Engine AlignmentIMPORTANT: The modified 91-57797A3 tool or the new tool 91-805475A1 will align allcurrent Alpha One as well as all older engines that used the older 91-57797A3.

CAUTIONTo avoid damage to gimbal bearing, engine coupler, or alignment tool:

� DO NOT attempt to force alignment tool!

� DO NOT raise or lower engine with alignment tool inserted (or partially inserted)in gimbal bearing or engine coupler.

1. Attempt to insert solid end of Quicksilver Alignment Tool through gimbal bearing and intoengine coupler splines.

2. If Quicksilver Alignment Tool will not insert easily, while observing the above precau-tions, CAREFULLY raise and lower front of engine with hoist. Continue as needed untiltool will SLIDE FREELY all the way in and out of engine coupler splines.

70013

ab

a - Alignment Tool (91-805475A1)b - Aligning End

72585

a

bc

a - Alignment Toolb - Gimbal Bearingc - Engine Coupler

IMPORTANT: Turn both front engine mount adjustment nuts an equal amount indirection required to align engine.

3. Adjust front engine mounts until they rest on boat stringers.


Page 2A-12 90-861329--1 MARCH 1999

4. Relieve hoist tension entirely and fasten both front mounts to boat stringer using appro-priate hardware (lag bolts or through-bolts, etc).

5. Recheck alignment with alignment tool. Tool must enter coupler splines freely. If not,readjust front mounts.

6. When alignment is correct, tighten locknut or nut with lockwasher on each mountsecurely.

22054

ab

c

de

b

a - Front Mountb - Attaching Bolts And Flat Washersc - Adjustment Nutd - Locknute - Jam Nut

7. Remove alignment tool if not already removed.

8. Tighten all exhaust system clamps securely as shown (use two clamps on eachconnection).

50633

a

a - Hose Clamps


90-861329--1 MARCH 1999 Page 2A-13

Engine ConnectionsIMPORTANT: When routing all wire harnesses and hoses, be sure they are routed andsecured to avoid coming in contact with hot spots on engine and avoid contact withmoving parts.

1. Connect seawater inlet hose to water tube at gimbal housing with hose clamp. Tightenclamp securely.

72614

ba

c

a - Water Inlet Tubeb - Hose Clampc - Seawater Inlet Hose

2. Connect instrument harness to engine harness with clamp. Tighten clamp securely.

50626

a

b

c

a - Engine Wiring Harnessb - Instrument Harnessc - Clamp


Page 2A-14 90-861329--1 MARCH 1999

3. Connect trim position sender leads from gimbal housing to leads from engine harness.

72992

a

b

c

d

a - BROWN/WHITE - From Engine Harnessb - BLACK - From Engine Harnessc - BLACK - From Transom Assemblyd - BLACK - From Transom Assembly

WARNINGBe careful when working on fuel system. Gasoline is extremely flammable andhighly explosive under certain conditions. Do not smoke or allow spark or openflame in area. Wipe up any spilled fuel immediately.

4. Connect fuel line from fuel tank(s) to engine. Make certain connections are secure.Check for leaks.

50738

b

a

a - Fuel Pumpb - Connect Flexible Fuel Inlet Line Here


90-861329--1 MARCH 1999 Page 2A-15

5. Connect throttle cable using hardware retained and adjust as follows:

a. Place remote control handle(s) in NEUTRAL, idle position.

IMPORTANT: Be sure that cable is routed in such a way as to avoid sharp bends and/or contact with moving parts. DO NOT fasten any items to throttle cable. Outer cablemust be free to move when cable is actuated.

75817

b

a

a - Anchor Bolt

b. Install cable end guide on throttle lever, then push cable barrel lightly toward throttlelever end. (This will place a slight preload on cable to avoid slack in cable whenmoving remote control lever.) Adjust barrel on throttle cable to align with anchor stud.

c. Secure throttle cable with hardware (retained) as shown. Tighten cable end guidelocknut until it contacts and then loosen one full turn. Tighten throttle cable anchorscrew securely. DO NOT OVERTIGHTEN, as cable must pivot freely.

75810

a

bc

de

a - Cable End Guideb - Throttle Cable Anchor Screwc - Cable Barreld - Cable End Guide Locknute - Throttle Lever


Page 2A-16 90-861329--1 MARCH 1999

d. Place remote control throttle lever in the wide-open-throttle (W.O.T.) position.Ensure that throttle shutters (valves) are completely open and throttle shaft levercontacts carburetor body casting.

e. Return remote control throttle lever to idle position and ensure that throttle lever con-tacts idle speed adjustment screw.

72283

b

c

a

e

d

a - Throttle Lever Tangb - Carburetor Bodyc - Idle Speed Adjustment Screwd - Wide Open Throttlee - Idle

50633

ba

a - Throttle Leverb - Idle Speed Adjustment Screw

IMPORTANT: Do not attach any accessory ground (–) wires to transom plate groundpoint. Accessory ground wires should only be attached to ground stud on engine.

6. Connect any grounding wires or accessories that have been disconnected.


90-861329--1 MARCH 1999 Page 2A-17

7. Connect MerCathode wires to MerCathode controller assembly as shown, if equipped.Apply a thin coat of Quicksilver Liquid Neoprene to all connections.

22232a b c d

a - ORANGE Wire - From Electrode on Transom Assemblyb - RED/PURPLE Wire - Connect Other End to Positive(+) Battery Terminalc - BLACK Wire - From Engine Harnessd - BROWN Wire - From Electrode on Transom Assembly

IMPORTANT: Adjust shift cables as outlined in appropriate Sterndrive ServiceManual.

8. Refer to appropriate Sterndrive Service Manual. Install and adjust drive unit and remotecontrol shift cables, using hardware retained.

IMPORTANT: After fluid hose installation in the following, bleed power steeringsystem as outlined in SECTION 1B - “Maintenance” or refer to appropriate SterndriveService Manual.

9. Connect power steering fluid hoses to control valve (large fitting first) as shown.

CAUTIONRoute hoses exactly as shown below. This will help avoid stress on the hose fittingsand will help avoid kinks in the hose.

IMPORTANT: Make hydraulic connections as quickly as possible to prevent fluidleakage.

IMPORTANT: Be careful not to cross-thread or overtighten fittings.

10. Torque fittings to 23 lb-ft (31 Nm).

73786

a

a - Power Steering Fluid Hose Fittings


Page 2A-18 90-861329--1 MARCH 1999

11. Connect battery cables to battery by FIRST connecting POSITIVE (+) battery cable(usually RED) to POSITIVE (+) battery terminal.

12. Tighten clamps securely.

13. Connect NEGATIVE (–) battery cable (usually BLACK) to NEGATIVE (–) batteryterminal.

14. Tighten clamp securely.

NOTE: Spray terminals with a battery connection sealant to help retard corrosion.


90-861329--1 MARCH 1999 Page 2A-19



Page 2A-20 90-861329--1 MARCH 1999


3A

181 CID (3.0L) 4 CYLINDER GM ENGINESERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 3A-1

ENGINESection 3A - 181 cid (3.0L) 4 Cylinder GM Engine

Table of Contents

Torque Specifications 3A-3. . . . . . . . . . . . . . . . . . Tools 3A-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Special Tools 3A-4. . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 3A-5. . . . . . . . . . Engine Specifications 3A-5. . . . . . . . . . . . . . . . . .

Cylinder Bore 3A-5. . . . . . . . . . . . . . . . . . . . . . Piston Clearance 3A-5. . . . . . . . . . . . . . . . . . . Piston Ring: Compression 3A-5. . . . . . . . . . . Piston Ring: Oil 3A-6. . . . . . . . . . . . . . . . . . . . . Piston Pin 3A-6. . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft 3A-6. . . . . . . . . . . . . . . . . . . . . . . . . Camshaft 3A-6. . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder Head 3A-7. . . . . . . . . . . . . . . . . . . . . . Valve System 3A-7. . . . . . . . . . . . . . . . . . . . . .

General 3A-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine Identification 3A-8. . . . . . . . . . . . . . . . Engine Rotation 3A-8. . . . . . . . . . . . . . . . . . . . Firing Order 3A-9. . . . . . . . . . . . . . . . . . . . . . . .

Priming Engine With Oil 3A-9. . . . . . . . . . . . . . . . Tool Required 3A-9. . . . . . . . . . . . . . . . . . . . . .

Bearing Failures 3A-10. . . . . . . . . . . . . . . . . . . . . Piston Failures 3A-12. . . . . . . . . . . . . . . . . . . . . . .

Pre-Ignition 3A-12. . . . . . . . . . . . . . . . . . . . . . . Detonation 3A-13. . . . . . . . . . . . . . . . . . . . . . . .

Engine Mounts 3A-14. . . . . . . . . . . . . . . . . . . . . . . Rocker Arm Cover 3A-15. . . . . . . . . . . . . . . . . . . .

Removal 3A-15. . . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-15. . . . . . . . . . . . . . . . . . . . . . . .

Push Rod Cover 3A-16. . . . . . . . . . . . . . . . . . . . . Removal 3A-16. . . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-16. . . . . . . . . . . . . . . . . . . . . . . .

Rocker Arm/Push Rod 3A-17. . . . . . . . . . . . . . . . Removal 3A-17. . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-17. . . . . . . . . . . . Installation 3A-18. . . . . . . . . . . . . . . . . . . . . . . .

Valve Adjustment 3A-18. . . . . . . . . . . . . . . . . . . . . Engine Not Running 3A-18. . . . . . . . . . . . . . . Engine Running 3A-19. . . . . . . . . . . . . . . . . . .

Hydraulic Valve Lifters 3A-20. . . . . . . . . . . . . . . . Locating Noisy Lifters 3A-20. . . . . . . . . . . . . . Removal 3A-21. . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-21. . . . . . . . . . . . Installation 3A-21. . . . . . . . . . . . . . . . . . . . . . . .

Valve Stem Oil Seal/Valve Spring 3A-22. . . . . . . Replacing Oil Seal (Head Installed) 3A-23. .

Cylinder Head 3A-24. . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-25. . . . . . . . . . . . Installation 3A-25. . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Head and Valve Conditioning 3A-26. . Disassembly 3A-26. . . . . . . . . . . . . . . . . . . . . . Cleaning 3A-26. . . . . . . . . . . . . . . . . . . . . . . . . Inspection 3A-27. . . . . . . . . . . . . . . . . . . . . . . . Rocker Arm Studs 3A-28. . . . . . . . . . . . . . . . . Valve Guide Bore Repair 3A-29. . . . . . . . . . . Valve Springs - Checking Tension 3A-30. . . . Valve Seats 3A-30. . . . . . . . . . . . . . . . . . . . . . . Reassembly 3A-31. . . . . . . . . . . . . . . . . . . . . .

Dipstick Specifications 3A-33. . . . . . . . . . . . . . . . All Engines 3A-33. . . . . . . . . . . . . . . . . . . . . . .

Oil Pan 3A-34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 3A-34. . . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-34. . . . . . . . . . . . . . . . . . . . . . . .

Oil Pump 3A-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 3A-35. . . . . . . . . . . . . . . . . . . . . . . . . Disassembly 3A-35. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-36. . . . . . . . . . . . Reassembly 3A-36. . . . . . . . . . . . . . . . . . . . . . Installation 3A-36. . . . . . . . . . . . . . . . . . . . . . . .

Torsional Damper 3A-37. . . . . . . . . . . . . . . . . . . . Removal 3A-37. . . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-37. . . . . . . . . . . . . . . . . . . . . . . .

Crankcase Oil Seal 3A-39. . . . . . . . . . . . . . . . . . . Replacing Oil Seal Without Removing Front Cover 3A-39. . . . . . . . . . . . . . . . . . . . . .

Crankcase Front Cover 3A-40. . . . . . . . . . . . . . . Removal 3A-40. . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-40. . . . . . . . . . . . Installation 3A-40. . . . . . . . . . . . . . . . . . . . . . . .

Flywheel and Engine Coupler 3A-41. . . . . . . . . . Removal 3A-41. . . . . . . . . . . . . . . . . . . . . . . . . Inspection 3A-41. . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-42. . . . . . . . . . . . . . . . . . . . . . . .

Rear Main Oil Seal 3A-43. . . . . . . . . . . . . . . . . . . Removal 3A-43. . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-43. . . . . . . . . . . . Installation 3A-43. . . . . . . . . . . . . . . . . . . . . . . .

Main Bearings 3A-44. . . . . . . . . . . . . . . . . . . . . . . Inspection 3A-44. . . . . . . . . . . . . . . . . . . . . . . . Checking Clearances 3A-45. . . . . . . . . . . . . . Main Bearing Replacement 3A-46. . . . . . . . . Connecting Rod Bearings 3A-47. . . . . . . . . . . Inspection and Replacement 3A-47. . . . . . . .

Connecting Rod/Piston Assembly 3A-49. . . . . . Removal 3A-49. . . . . . . . . . . . . . . . . . . . . . . . . Disassembly 3A-49. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-50. . . . . . . . . . . . Reassembly 3A-51. . . . . . . . . . . . . . . . . . . . . . Installation 3A-53. . . . . . . . . . . . . . . . . . . . . . . .

181 CID (3.0L) 4 CYLINDER GM ENGINE SERVICE MANUAL NUMBER 26

Page 3A-2 90-861329--1 MARCH 1999

Table of Contents (continued)

Crankshaft 3A-55. . . . . . . . . . . . . . . . . . . . . . . . . . Removal 3A-55. . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-56. . . . . . . . . . . . Installation 3A-56. . . . . . . . . . . . . . . . . . . . . . . .

Crankshaft Sprocket 3A-57. . . . . . . . . . . . . . . . . . Removal 3A-57. . . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-57. . . . . . . . . . . . . . . . . . . . . . . .

Camshaft 3A-58. . . . . . . . . . . . . . . . . . . . . . . . . . . Measuring Lobe Lift 3A-58. . . . . . . . . . . . . . . . Removal 3A-58. . . . . . . . . . . . . . . . . . . . . . . . . Inspection 3A-59. . . . . . . . . . . . . . . . . . . . . . . . Camshaft Gear Replacement 3A-60. . . . . . . Installation 3A-60. . . . . . . . . . . . . . . . . . . . . . . .

Camshaft Bearings 3A-62. . . . . . . . . . . . . . . . . . . Removal 3A-62. . . . . . . . . . . . . . . . . . . . . . . . . Inspection 3A-62. . . . . . . . . . . . . . . . . . . . . . . . Installation 3A-62. . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Block 3A-64. . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 3A-64. . . . . . . . . . . .

Oil Filter By-Pass Valve 3A-68. . . . . . . . . . . . . . . Inspection and/or Replacement 3A-68. . . . . .


90-861329--1 MARCH 1999 Page 3A-3


Fastener Location lb-in. lb-ft Nm

Camshaft Sprocket Bolts 80 9

Connecting Rod Cap Nuts 45 61

Cylinder Head Bolts 901 122

Distributor Clamp 20 27

Engine Coupler to Flywheel 35 47

Flywheel Housing to Block 21 28

Flywheel to Crankshaft Bolts 65 88

Front Cover Bolts 27-35 3.4

Front Mount to Block 21 28

Main Bearing Cap Bolts 65 88

Center 20-252 27-34Manifold to Head

Outer 15-20 20-27

Oil Pan Bolts-Crankcase 80 9

Oil Pan Bolts-to Front Cover 45 5

Oil Pan Studs to Oil Seal Retainer or Crankcase 15 1.7

Oil Pump Cover 72 8

Oil Pump to Block 120 14

Oil Pump Pickup 60 7

Rocker Arm Cover and Bolts 40 4.5

Rocker Arm Nuts 3/4 Turn Down From ZeroLash

Push Rod Cover Bolts 40 4.5

Crankshaft Rear Oil Seal Retainer Nuts 150-180 17-20

Spark Plugs 22 30

Starter Motor to Block 37 50

Timing Gear Cover 72 8

Torsional Damper Bolt 50 68

Water Pump to Block 15 20

1 Retorque after first 20 hours of operation.2 Retorque after first start-up.


Page 3A-4 90-861329--1 MARCH 1999

Tools

Description Parts Number

Piston Ring Expander 91-24697

Torch Lamp 91-63209

Special Tools

KENT MOORE SPECIAL TOOLS

Kent-Moore Special Tools29784 Little Mack

Roseville, MI 48066Phone: (313) 574-2332


Valve Spring Compressor (Head on) J5892

Valve Spring Compressor (Head off) J8062

Valve Stem Seal Tester J23738-A

Valve Guide Reamer (Standard) J8814

Valve Guide Reamer (.015 in. oversize) J5830-02

Rocker Arm Stud Remover J5802-01

Rocker Arm Stud Installer J6880

Stud Bore Reamer (.003 in. oversize) J5715

Stud Bore Reamer (.013 in. oversize) J6036

Carbon Remover Brush J8089

Piston Support Tool J5910-04

Piston Pin Tool J24086-B

Piston Ring Groove Cleaner J3936-03

Piston Ring Compressor J8037

Connecting Rod Guide Tool (3/8-24) J5239

Cylinder Bore Checker J8087

Oil Pump Suction Pipe Installer J8369

Timing Cover Seal Aligner J23042-B

Cam Lobe Lift Indicator J8520

Camshaft Bearing Installer/Remover Tool J6098-01

Distributor Shaft Lower Bearing Installer/Remover

J9534-01

Pulley Hub Puller J6978-E

Pulley Hub Installer J5590

Universal Torsional Damper Remover J24420-B


90-861329--1 MARCH 1999 Page 3A-5

Lubricants/Sealants/Adhesives


Quicksilver Perfect Seal 92-34227--1

Quicksilver 2-4-C Marine Lubricant withTeflon

92-825407A3

Quicksilver RTV Sealer 92-809826

Engine Specifications

NOTICE

Unit Of Measurement: U.S. Inches (Millimeters)

Model 3.0L

Displacement 181 cid (3.0L)

Cylinder Bore

Diameter 3.9995-4.0025 (101.588-101.790)

Production .0005 (0.012) MaxOut of Round

Service .002 (0.05) Max

ProductionThrustSide

.0005 (0.012) Max

TaperProduction

Relief Side .0005 (0.012) Max


Piston Clearance

Production .0025-.0035 (0.064-0.088) Max


Piston Ring: Compression

Top

Groove ClearanceProduction

2nd.0012-.0029 (0.030-0.073)


Top

GapProduction

2nd.010-.020 (0.254-0.762)



Page 3A-6 90-861329--1 MARCH 1999

Piston Ring: Oil

Production .001-.006 (0.026-0.152)Groove

Clearance ServiceLimit

.007 (0.17) Max

Production .010-.030 (0.254-0.762) MaxGap Service

Limit.040 (1.01) Max

Piston Pin

Diameter .9270-.9271 (23.546-23.550)

Production .0003-.0006 (0.008-0.016)Clearance Service

Limit.001 (0.02) Max

Fit in Rod .0008-.0019 (0.020-0.050) Interference

Crankshaft

Diameter 2.2979-2.294 (58.367-58.404)Main Production .0002 (0.005) Max

Journal TaperService .001 (0.02) Max

Out of Production .0002 (0.005) MaxOut ofRound Service .001 (0.02) Max

Production No.1-No.4 .001-.0024 (0.025-0.060)Main Service No.5 .0016-.0035 (0.041-0.088)

BearingClearance Production No.1-No.4 .001-.0025 (0.03-0.06)Clearance

Service No.5 .002-.0035 (0.05-0.08)

Crankshaft End Play .002-.006 (0.05-0.15)

Diameter 2.09980-20995 (53.289-53.327)

Production .0003 (0.007) Max

CrankpinTaper


Out of Production .0002 (0.51) MaxOut ofRound Service .001 (0.02) Max

Rod Production .0017-.0027 (0.044-0.0686)Bearing

Clearance Service

Rod Size Clearance .006-.017 (0.153-0.4318) Max

Camshaft

Intake .2529 (6.425)Lobe Lift (Max.)

Exhaust .2529 (6.425)

Journal Diameter 1.8677-18697 (47.440-47.490)

Camshaft End Play .003-.008 (0.08-0.2032) Max


90-861329--1 MARCH 1999 Page 3A-7

Cylinder Head

Gasket Surface Flatness .003-.008 in any 6 in. (152) or .007(0.15) Overall Max

Valve System

Lifter Hydraulic

Rocker Arm Ratio 1.75 to 1

Collapsed Tappet Gap 3/4 Turn Down from Zero Lash

Intake 45°Face Angle

Exhaust 45°Seat Angle (Intake & Exhaust) 46°

Seat Runout (Intake & Exhaust) .002 (0.05) Max

Intake 1/16 (.0625 in.) (1.16 mm)Seat Width

Exhaust 1/16-5/64 [.0625-.07812 in.] (1.6-2.0 mm)

Intake .0010-.0027 (0.025-0.069)

StemProduction

Exhaust .0007-.0027 (0.018-0.069)StemClearance Intake .003 (0.09) Max

ServiceExhaust .004 (0.11) Max

Free Length 2-1/16 in. (52 mm)

ValveClosed

100-110 lb. (136-149 N) at 1-19/32 in. (41 mm)

SpringPressure

ValveOpen

208-220 lb. (282-300 N) at 1-7/32 in. (31 mm)

Installed±

IntakeHeight ±.031(8) Exhaust

(1/32) 1.6562 (42)

Internal Damper None

General

Some of the repairs in this section must be completed with engine removed from boat.Engine removal depends upon type of repair and boat design. Place engine on repair standfor major repairs.

When engine removal is not required, make certain that battery cables are disconnectedat the battery prior to performing any on-board engine repair procedure.

Lubricate all moving parts (during reassembly) with engine oil. Apply Quicksilver PerfectSeal on threads of and under heads of cylinder head bolts, and on threads of all cylinderblock external bolts, screws and studs.

Model No. of Cylinders cu-in./liters Displacement

MCM 3.0L 4 181 (3L)


Page 3A-8 90-861329--1 MARCH 1999

Engine IdentificationThe MerCruiser Model can be determined by looking at the LAST TWO LETTERS of theengine code stamped into the cylinder block. This code number is stamped on allMerCruiser power packages and replacement partial engines, but not replacement cylinderblock assemblies.

If the engine serial number and/or model decals are missing, the engine code letters mayhelp in determining the engine models.

a74520

G.M. Engine Code Location 3.0L - RX (12-3/4 in. or 324 mm flywheel) - S/N 0L096999 and belowRP (14 in. or 356 mm flywheel) - S/N 0L097000 and above

a - 4 Cylinder-In-Line Engine Code (Next To Distributor)

Engine RotationEngine rotation terminology at times has caused confusion. To clarify, engine rotation isdetermined by observing flywheel rotation from the rear (transmission or sterndrive end) ofthe engine looking forward (water pump end).

PROPELLER ROTATION IS NOT NECESSARILY THE SAME as engine rotation. Do notrely on propeller rotation in determining engine rotation.

72001

a

a - Left-Hand Rotation (CCW)


90-861329--1 MARCH 1999 Page 3A-9

Firing Order

50683


Priming Engine With Oil

IMPORTANT: This applies to all power packages that have not been run within 6months, replacement of partial engines or after rebuilding an engine.

Tool Required

71089

Remote Starter Kit (91-52024A1)

1. Fill crankcase to proper level with the recommended engine oil.

2. Remove spark plugs.

3. Leave ignition key in “OFF” position.

4. Connect remote starter switch to large 12 V terminal (RED battery cable) and small ter-minal (RED/YELLOW) wire on starter motor.

a. If remote starter switch is not available, disconnect PURPLE wire from ignition coilbefore using key switch to crank the engine over. Tape terminal on PURPLE wire toprevent it from touching ground.

5. Crank engine for 15 seconds, then allow starter motor to cool down for 1 minute. Thisshould prevent starter motor from overheating.

6. Repeat this process until a total of 45 seconds of cranking time is achieved.

7. Remove remote starter switch.

a. If key switch was used, reconnect PURPLE wire to ignition coil.

8. Install spark plugs and wires

9. Supply cooling water to seawater pump and start motor.


Page 3A-10 90-861329--1 MARCH 1999

Bearing Failures

70436a b

Scratched By Dirta - Scratchesb - Dirt Imbedded In Bearing Material

70436a

Tapered Journala - Overlay Gone From Entire Surface

70436aLack Of Oil

a - Overlay Worn Off

70436a

Radius Ridea - Worn Area


90-861329--1 MARCH 1999 Page 3A-11

70436

a

Improper Seatinga - Bright Or Polished Sections

70436a

Fatigue Failurea - Craters or Pockets


Page 3A-12 90-861329--1 MARCH 1999

Piston Failures

Pre-IgnitionPre-ignition is abnormal fuel ignition, caused by combustion chamber hot spots. Control ofthe start of ignition is lost, as combustion pressure rises too early, causing power loss andrough running. The upward motion on the piston is opposed by the pressure rise. This canresult in extensive damage to the internal parts from the high increase in combustion cham-ber temperature.

72424

Pre-Ignition Damage

CAUSES

1. Hot spots in the combustion chamber from glowing deposits (due in turn to the use ofimproper oils and/or fuels).

2. Overheated spark plug electrodes (improper heat range or defective plug).

3. Any other protuberance in the combustion chamber, such as an overhanging piece ofgasket, an improperly seated valve or any other inadequately cooled section of materialwhich can serve as a source.

Engine failures that result from the foregoing conditions are beyond the control of MercuryMarine. No warranty will apply to failures which occur under these conditions.


90-861329--1 MARCH 1999 Page 3A-13

DetonationDetonation, commonly called “fuel knock,” “spark knock” or “carbon knock,” is abnormalcombustion of the fuel which causes the fuel to explode violently. The explosion causesoverheating or damage to the spark plugs, pistons, valves and, in severe cases, results inpre-ignition.

CAUSES

IMPORTANT: Use of improper fuels will cause engine damage and poor performance.

1. Use of low octane gasoline is one of the most common causes of detonation. Even withhigh octane gasoline, detonation could occur if engine maintenance is neglected.

2. Over-advanced ignition timing.

3. Lean fuel mixture at or near full throttle (could be caused by carburetor or leaking intakemanifold).

4. Cross-firing spark plugs.

5. Excess accumulation of deposits on piston and/or combustion chamber (results inhigher compression ratio).

6. Inadequate cooling of engine by deterioration of cooling system.

Engine failures that result from the foregoing conditions are beyond the control ofMerCruiser. No warranty will apply to failures which occur under these conditions.

72425

Detonation Damage

72315

a b

c d

a - Spark Occursb - Combustion Beginsc - Combustion Continuesd - Detonation Occurs


Page 3A-14 90-861329--1 MARCH 1999

Engine Mounts

74275

Front Mount

72318a

Rear Mount/Flywheel Housinga - Press Mount Out With Press


90-861329--1 MARCH 1999 Page 3A-15

Rocker Arm Cover

RemovalIt may be necessary to remove exhaust manifold before removing rocker arm cover. Referto SECTION 7B for removal.

1. Disconnect crankcase ventilation hose.

2. Remove any items that interfere with the removal of rocker arm covers.

IMPORTANT: DO NOT pry rocker arm cover loose. Gaskets, which may adhere to cyl-inder head and rocker arm cover, may be loosened by bumping end of rocker coverfrom the rear with palm of hand or a rubber mallet.

3. Remove rocker arm cover.

Installation1. Clean sealing surfaces on cylinder head and rocker arm cover with degreaser.

2. Place new rocker arm cover gasket in position in rocker arm cover.

3. Install rocker arm cover. Torque bolts to 40 lb-in. (4.5 Nm).

4. Install exhaust manifolds.

5. Install any items which were removed to allow removal of rocker arm covers.

6. Connect crankcase ventilation hose to rocker arm cover.


Page 3A-16 90-861329--1 MARCH 1999

Push Rod Cover

Removal1. Remove the pushrod cover bolts.

2. Remove the pushrod cover.

3. Remove the gasket.

76247

Installation1. Clean sealing surfaces on pushrod cover with degreaser.

2. Install new pushrod cover gasket in position.

3. Install pushrod cover. Torque bolts to 40 lb-in. (4.5 Nm).


90-861329--1 MARCH 1999 Page 3A-17

Rocker Arm/Push Rod

74287

e

a

b

c

d

Valve Mechanisma - Nutb - Ball Unitc - Rocker Armd - Push Rode - Rocker Arm Stud

RemovalNOTE: When servicing only one cylinder’s rocker arms, bring that cylinder’s piston up toTDC before removing rocker arms. When servicing all rocker arms, bring No. 1 piston upto TDC before removing rocker arms.

1. Remove rocker arm covers as outlined.

2. Remove rocker arm assemblies and push rods.

76232

IMPORTANT: Place rocker arm assemblies and push rods in a rack for reassemblyin their original locations.

Cleaning and Inspection1. Clean parts with solvent and dry with compressed air.

2. Inspect all contact surfaces for wear. Replace all damaged parts.


Page 3A-18 90-861329--1 MARCH 1999

InstallationIMPORTANT: When installing rocker arms and rocker arm balls, coat bearing sur-faces of rocker arms and rocker arm balls with engine oil.

1. Install push rods in their original locations. Be sure push rods seat in lifter socket.

2. Install rocker arms, rocker arm balls and rocker arm nuts in their original locations.

76232

3. Turn nut down 1/4 additional turn and pause 10 seconds until engine runs smoothly.Repeat additional 1/4 turns, pausing 10 seconds each time, until nut has been turneddown 3/4 turn from zero lash position.

4. Adjust carburetor idle speed and mixture.

Valve Adjustment

Engine Not RunningWith valve cover removed, adjust valves when lifter is on low part of camshaft lobe, asfollows:

1. Crank engine with starter or turn over in normal direction of rotation until mark ontorsional damper lines up with center “0” mark on timing tab, and engine is in No. 1 firingposition. This may be determined by placing fingers on No. 1 valve as mark. If valvesmove as mark comes up to timing tab, engine is in No.4 firing position and should beturned over one more time to reach No. 1 position.

50770

Typical


90-861329--1 MARCH 1999 Page 3A-19

2. With engine in No. 1 firing position as determined above, the following valves may beadjusted:

• No. 1 Cylinder - Exhaust and Intake

• No. 2 Cylinder - Intake

• No. 3 Cylinder - Exhaust


3. Loosen adjusting nut until lash is felt at push rod, then tighten adjusting nut until all lashis removed. This can be determined by moving push rod up and down while turningadjusting nut until all play is removed.

72300

4. Hydraulic lifters can be adjusted by tightening adjustment nut an additional 3/4-turn.Valve lash should be checked after engine has run and reached operating temperature.

5. Crank engine one revolution until pointer “0” mark and torsional damper mark are againin alignment. This is No. 4 firing position. With engine in this position, the following valvesmay be adjusted:




6. Repeat steps 3-4 to adjust other valves.

7. Install Distributor cap, spark plug wires and coil lead.

8. Install rocker arm cover; torque to 40 lb-in. (4.5 Nm).

Engine RunningFollowing procedure should be completed only if readjustment is required.

1. Run engine until it reaches normal operating temperature, then remove valve cover.

2. With engine running at idle, loosen valve rocker arm nut until valve rocker arm starts toclatter.

3. Turn rocker arm nut down slowly until clatter just stops. This is zero lash position.

4. Tighten nut 1/4 additional turn and pause 10 seconds until engine runs smoothly. Repeatadditional 1/4 turns, pausing 10 seconds each time, until nut has been tightened 3/4 turnfrom zero lash position.


Page 3A-20 90-861329--1 MARCH 1999

IMPORTANT: The following preload adjustment must be done slowly to allow lifter toadjust itself, thus preventing possibility of the valve head contacting the top ofpiston, which may result in internal damage and/or bent push rods.

5. Repeat Steps 2-4 to adjust other valves.

6. Install rocker arm cover, torque to 40 lb-in. (4.5 Nm).

7. Adjust carburetor idle mixture and idle speed. Check for leaks.

Hydraulic Valve Lifters

Hydraulic valve lifters require little attention. Lifters are extremely simple in design.Normally, readjustments are not necessary and servicing requires only that care andcleanliness be exercised in the handling of parts.

Locating Noisy LiftersLocate a noisy valve lifter by using a piece of garden hose approximately 4 ft (1.2 m) inlength. Place one end of hose near end of each intake and exhaust valve, with other endof hose to the ear. In this manner, sound is localized, making it easy to determine which lifteris at fault.

Another method is to place a finger on face of valve spring retainer. If lifter is not functioningproperly, a distinct shock will be felt when valve returns to its seat.

General types of valve lifter noise are as follows:

1. Hard rapping noise - usually caused by plunger becoming tight in bore of lifter body sothat return spring cannot push plunger back up to working position. Probable causesare:

• Excessive varnish or carbon deposit, causing abnormal stickiness.

• Galling or “pickup” between plunger and bore of lifter body, usually caused by an abra-sive piece of dirt or metal wedged between plunger and lifter body.

2. Moderate rapping noise - probable causes are:

• Excessively high leakdown rate.

• Leaky check valve seat.

• Improper adjustment.

3. General noise throughout valve train - this will, in most cases, be a definite indicationof insufficient oil supply or improper adjustment.

4. Intermittent clicking - probable causes are:

• A microscopic piece of dirt momentarily caught between ball seat and check valve ball.

• In rare cases, ball itself may be out of round or have a flat spot.

• Improper adjustment.

In most cases, where noise exists in one or more lifters, all lifter units should be removed,disassembled, cleaned in solvent, reassembled and reinstalled in engine. If dirt, corrosion,carbon, etc., exists in one unit, it probably exists in all units. It would only be a matter of timebefore all lifters caused trouble.


90-861329--1 MARCH 1999 Page 3A-21

Removal1. Remove as previously outlined:

a. Rocker arm covers.

b. Push rod cover.

IMPORTANT: Keep valve push rod and hydraulic lifter from each valve together as amatched set and mark or store them so they can be reinstalled in the same locationlater.

c. Rocker arm assemblies and push rods.

2. Make matching marks on all lifters as to location and orientation in bores, to allow reas-sembly in exact position on camshaft lobes (so that the roller’s bearing and roller will rollin the same direction on the same lobe, if reused). Remove valve lifters.

Cleaning and Inspection1. Thoroughly clean all parts in cleaning solvent and inspect them carefully.

2. If any parts are damaged or worn, entire lifter assembly should be replaced.

3. If outer lifter body wall is scuffed or worn, inspect cylinder block lifter bore.

4. If push rod seat is scuffed or worn, inspect push rod.

InstallationIMPORTANT: It is recommended that the engine oil be changed and a new oil filter beinstalled whenever servicing valve lifters or camshaft

IMPORTANT: Before installing lifters, coat the lifter with engine oil. If new lifters ora new camshaft have been installed, an additive containing EP lube (such as GeneralMotors Cam and Lifter Prelube or equivalent) should be poured over camshaft lobesbefore installing lifters.

IMPORTANT: DO NOT install used valve lifters if a new camshaft has been installed.

1. Install valve lifters into bores.

2. Install push rod cover, using new gaskets and torque to specification.

3. Install distributor, positioning rotor to number 1 cylinder position, then connect primarylead at coil.

4. Install distributor cap and spark plug wires.

5. Adjust valves to specifications.

6. Install rocker arm cover, torque tp 40 lb-in. (4.5 Nm).

7. Adjust ignition timing, carburetor idle speed and mixture.


Page 3A-22 90-861329--1 MARCH 1999

Valve Stem Oil Seal/Valve Spring

76248

a

b

c

d

e

f

a - Keys (2 per Valve)b - Capc - Seald - Valve Spring Shielde - Valve Springf - Valve


90-861329--1 MARCH 1999 Page 3A-23

Replacing Oil Seal (Head Installed)1. Remove rocker arm cover.

2. Remove spark plug, rocker arm and push rod on cylinder to be serviced.

3. Place piston for that cylinder at TDC to prevent valves from dropping into the cylinder.

4. Compress valve spring with tool (J-5892) and remove valve keys, valve spring cap,spring shield and valve spring.

72881a

b

a - Valve Spring Compressor (J-5892)b - Rocker Arm Nut

5. Remove valve stem oil seal.

6. To install, set valve spring, (close, coiled end of spring is installed against cylinder head)valve shield and valve cap in place. Compress spring with tool (J-5892) and install oilseal in lower groove of stem, making sure that seal is flat and not twisted.

NOTE: A light coat of oil on seal will help prevent twisting when compressor tool is released.

IMPORTANT: Do not turn crankshaft while valve springs, retainers, and locks areremoved or valves will fall into cylinder.

7. Install valve keys and release compressor tool. Be sure that keys seat properly in uppergroove of valve stem.

8. Install and adjust valve mechanism.

9. Install push rods and rocker arm assemblies.

10. Torque rocker arm nuts as described in “Specifications.”

11. Install rocker arm cover and torque to 40 lb-in. (4.5 Nm).

12. Install spark plug and torque to 22 lb-ft (30 Nm).

13. Repeat steps 2 through 8 for other cylinders.


Page 3A-24 90-861329--1 MARCH 1999

Cylinder Head

1

26

5

3

49

10 7

8

Cylinder Head Torque Sequence

1. Drain engine cooling system.

2. Remove as outlined:

a. Exhaust manifolds.

b. Intake manifold.

c. Rocker arm cover.

d. Pushrod cover.

e. Rocker arm assemblies and push rods (keep in order for reassembly in their originallocations).

76232

f. Any components attached to front or rear of cylinder head.

g. Spark plugs.

h. Head bolts.

CAUTIONThe head gasket may be holding cylinder head to block. Use care when prying offcylinder heads. DO NOT damage gasket surfaces. DO NOT drop cylinder heads.

3. Place cylinder head on wooden blocks to prevent damage to gasket surfaces.


90-861329--1 MARCH 1999 Page 3A-25

Cleaning and Inspection1. Clean gasket material and sealer from engine block and cylinder heads.

2. Inspect sealing surfaces for deep nicks and scratches.

3. Inspect for corrosion around cooling passages.

4. Clean head bolt threads and engine block bolt hole threads, making sure no dirt, old oilor coolant remains.

Installation

CAUTIONWhen using ribbed stainless steel head gaskets, apply a thin coating of QuicksilverPerfect Seal to both sides of gasket. Too much sealer may hold gasket away fromhead or block causing leakage. DO NOT use sealer on graphite composition headgaskets.

1. Place head gasket in position over dowel pins.

2. Carefully set cylinder head in place over dowel pins.

3. Coat threads of head bolts with Quicksilver Perfect Seal and install finger-tight.

4. Torque head bolts to 90 lb-ft (122 Nm).

5. Install push rods, rocker arm assemblies and lifter restrictors in their original positions.

6. Torque rocker arm nuts to 20 lb-ft (27 Nm).

7. Install as outlined:

a. Intake/exhaust manifold.

b. Rocker arm cover.

c. Spark plugs.

d. Any components removed from front or rear of cylinder heads.

8. Follow procedures in SECTION 6A or 6B of this manual:

Seawater Cooled Models: Provide for adequate water supply to seawater pickup (seeSECTION 6A).

Closed Cooled Models: Refill closed cooling section (see SECTION 6B) and provide ade-quate water supply to seawater pickup.

CAUTIONEnsure that cooling water supply is available before starting the engine.

9. Start engine, set timing, set idle speed and check for leaks.


Page 3A-26 90-861329--1 MARCH 1999

Cylinder Head and Valve Conditioning

Disassembly1. Using valve spring compressor, compress valve spring (J-8062) and remove valve

locks. Slowly release tool.

2. Remove all valve components.

3. Remove valves from cylinder head and place in a rack, in order, for reassembly in theiroriginal locations.

72333

a

a - Valve Spring Compressor (J-8062)

Cleaning1. Clean push rods and rocker arm assemblies.

2. Clean carbon from valves using tool (J-80890).

3. Clean gasket material from cylinder head mating surfaces.

4. Clean all carbon from combustion chambers and valve ports using carbon removerbrush.

74274

a

a - Carbon Remover Brush (J-8089)


90-861329--1 MARCH 1999 Page 3A-27

5. Thoroughly clean valve guides with valve guide cleaner (J-8101).

74286

a

a - Valve Guide Cleaner (J-8101)

Inspection1. Inspect cylinder head for cracks in exhaust ports, water jackets and combustion cham-

bers (especially around spark plug holes and valve seats). Replace heads if any cracksare found.

2. Inspect cylinder head gasket surface for burrs, nicks, erosion or other damage. Checkflatness of cylinder head gasket surface, using a machinist’s straight edge and feelergauges as shown. Take measurements diagonally across head (both ways) and straightdown center head. Refer to “Specifications.”

72885b

a

a - Straight Edgeb - Feeler Gauge

IMPORTANT: Cylinder head-to-block gasket surface should be resurfaced if warpedmore than specified. When head resurfacing is required, cylinder head-to-intakemanifold gasket surface on head must be milled to provide proper alignmentbetween intake manifold and head.

3. Inspect valves for burned heads, cracked faces or damaged stems.

IMPORTANT: Excessive valve stem to bore clearance will cause excessive oilconsumption and possible valve breakage. Insufficient clearance will result in noisyand sticky valves.

4. Measure valve stem clearance as follows:

a. Attach a dial indicator to cylinder head, positioning it against the valve stem andclose to the valve guide.

b. Holding valve head off seat about 1/16 in. (2 mm), move valve stem back and forthin direction shown. Compare stem clearance with specifications.


Page 3A-28 90-861329--1 MARCH 1999

c. If clearance exceeds specifications, it will be necessary to ream valve guides foroversized valves, as outlined under “Valve Guide Bore Repair.”

72336

c

b

a

a - Valve Stemb - Dial Indicatorc - Valve Guide

Rocker Arm StudsRocker arm studs with damaged threads or with loose fit in cylinder heads should bereplaced with new, oversize studs. Studs may be installed after reaming holes as follows:

1. Drain water from cylinder block.

2. Remove old stud by placing Tool J-5802-1 over stud, installing nut and flat washer andturning the nut to remove stud.

74288

a

a - Tool J-5802-01


90-861329--1 MARCH 1999 Page 3A-29

3. Ream hole for oversize stud with Tool J-5715 for .003 in. oversize or Tool J-6036 for .013in. oversize.

74289

a

a - Reamer Tool J-5715

IMPORTANT: Do not attempt to install an oversize stud without reaming stud hole.

4. Coat press-fit area of stud with Perfect Seal. Install new stud, using Tool J-6880 as aguide. Gauge should contact head.

Valve Guide Bore RepairIMPORTANT: Be sure to measure valve stem diameter of both the intake and exhaustvalve, as valve stem diameter may or may not be the same for both valves.

If .015 in. oversize valve stems are required, ream valve guide bores for oversize valves,as follows:

1. Measure valve stem diameter of old valve being replaced and select proper size valveguide reamer from chart below.

2. Ream valve guide bores, as shown.

72886

3. Remove the sharp corner created by reamer at top of valve guide.


Page 3A-30 90-861329--1 MARCH 1999

Valve Springs - Checking TensionUsing valve spring tester, as shown, check valve spring tension with dampers removed.Refer to “Specifications.”

IMPORTANT: Springs should be replaced if not within 10 lbs. (44 N) of specifiedtension.

a

b

72308

a - Valve Spring Tester (J-8056)b - Torque Wrench

Valve SeatsValve seat reconditioning is very important, since seating of valves must be perfect forengine to deliver maximum power and performance.

Another important factor is valve head cooling. Good contact between each valve and itsseat in head is important to ensure that heat in valve head will be properly dispersed.

Several different types of equipment are available for reseating valve seats. Equipmentmanufacturer’s recommendations should be followed carefully to attain proper results.

Regardless of type of equipment, however, it is essential that valve guide bores be free fromcarbon or dirt to achieve proper centering of pilot in valve guide and ensure concentricity.

72338a

a - Check Valve Seat Concentricity

Valves that are pitted must be refaced to the proper angle. Valve stems which show exces-sive wear or valves that are warped excessively must be replaced. When a valve head thatis warped excessively is refaced, a knife edge will be ground on part or all of the valve headdue to the amount of metal that must be removed to completely reface. Knife edges leadto breakage, burning or pre-ignition due to heat localizing on this knife edge. If the edge ofthe valve head (margin) is less than 1/32 in. (0.8 mm) after grinding, replace the valve.


90-861329--1 MARCH 1999 Page 3A-31

Several different types of equipment are available for refacing valves. The recommendationof the manufacturer of the equipment being used should be carefully followed to attainproper results.

50695

Exhaust Intakea - .372 In. (9.45 mm)b - 1/32 [.031] In. (0.79 mm) Min.c - .341 In. (8.16 mm)d - 1/32 [.031] In. (0.79 mm) Min.

Reassembly1. Lubricate valve guides and valve stems with engine oil.

2. Install each valve in the port from which it was removed or to which it was fitted.

3. Install valve guide seal (intake valve only) over valve stem and push down until seatedagainst head.

4. Set valve spring (with damper installed) and cap in place.

5. Place retainer on intake valve and/or rotator on exhaust valve.

6. While compressing valve spring with valve spring compressor, install oil seal in lowergroove of valve stem, making sure seal is not twisted. A light coating of oil will helpprevent twisting.

72884

a

V6 Showna - Valve Spring Compressor (J-8062)


Page 3A-32 90-861329--1 MARCH 1999

7. Install valve locks (grease may be used to hold them in place) and slowly release tool,making sure locks seat properly in upper grooves of valve stem.

76249

�

�

�

��

�

�

�

�

1 - Valve Locks2 - Retainer3 - Rotator4 - Cap5 - Valve Guide Oil Seal6 - Valve Stem Oil Seal7 - Outer Spring8 - Intake Valve9 - Exhaust Valve


90-861329--1 MARCH 1999 Page 3A-33

8. Check installed height of valve springs using a narrow, thin scale. Measure from springseat to top of valve spring, as shown. If measurement exceeds specified height, installa valve spring shim and recheck. DO NOT shim valve springs to give an installed heightless than the minimum specified.

05037

72339

a

b

Checking Valve Spring Installed Heighta - Cut Out This Portionb - Valve Spring Installed Height

Dipstick SpecificationsAll Engines

NOTICE

Unit Of Measurement: U.S. inches (millimeters)

1/2(13)

25-7/16(646)

3/4(19)

26-7/8(682)a

b

72887

41092-1 MCMa - Fullb - Add


Page 3A-34 90-861329--1 MARCH 1999

Oil Pan

a

a - Oil Pan Gasket

Removal1. Disconnect battery.

NOTE: Removal of engine from boat may be required.

2. Drain crankcase oil.

3. Remove starter motor.

4. Remove oil pan screws, oil pan and gasket(s).

Installation1. Clean sealing surfaces of engine block and oil pan.

2. Apply a small amount of Quicksilver RTV Sealer to joints of rear seal retainer and jointsof front cover.

IMPORTANT: Quicksilver RTV Sealer sets up in about 15 minutes. Be sure to com-plete assembly promptly.

3. Install oil pan gasket in position as shown.

NOTE: A one-piece oil pan gasket may be reused if it is still pliable and is not cracked, tornor otherwise damaged.

4. Install oil pan. Starting from the center and working outward in each direction, tighten1/4-20 threaded fasteners to 80 lb-in. (9 Nm) and 5/16-18 threaded fasteners to 165 lb-in. (19 Nm).

5. Install dipstick tube and dipstick.

6. Fill crankcase with required quantity of oil of specified viscosity. See SECTION 1B“Maintenance.”


90-861329--1 MARCH 1999 Page 3A-35

Oil Pump

The oil pump consists of two gears and a pressure regulator valve enclosed in a two-piecehousing. Oil pump is driven by distributor shaft which is driven by a helical gear on camshaft.

Removal1. Remove oil pan as previously outlined.

2. Remove gasket carefully as the one-piece gasket for the oil pan may be reused if stillpliable and not cracked, torn, etc.

3. Remove oil pump.

76234

a

a - Oil Pump

Disassembly1. Remove pump cover.

IMPORTANT: Mark gear teeth for reassembly with same teeth indexing.

2. Remove idler gear and drive gear from pump body.

3. Remove retaining pin, spring, and pressure regulator valve from pump cover.

IMPORTANT: Do not remove pickup screen and pipe assembly, unless replacementis necessary. Loss of press fit condition could result in an air leak and loss of oil pres-sure.

IMPORTANT: Do not disturb pickup screen on pipe. This is serviced as an assembly.

4. If pickup screen and pipe assembly requires replacement, mount pump in a soft-jawedvise and extract pipe from pump.


Page 3A-36 90-861329--1 MARCH 1999

Cleaning and Inspection1. Wash all parts in cleaning solvent and dry with compressed air.

2. Inspect pump body and cover for cracks or excessive wear.

3. Inspect pump gears for damage and excessive wear.

4. Check for loose drive gear shaft in pump body.

5. Inspect inside of pump cover for wear that would permit oil to leak past ends of gears.

IMPORTANT: Pump gears and body are not serviced separately. If pump gears orbody are damaged or worn, replacement of entire oil pump assembly is necessary.

6. Inspect pickup screen and pipe assembly for damage to screen and pipe.

7. Check pressure regulator valve for fit.

Reassembly

CAUTIONBe careful of twisting, shearing or collapsing pipe while installing in pump. Pickupscreen must be parallel to oil pan bottom when oil pump is installed.

If pickup screen and pipe assembly was removed, mount pump in a soft-jawed vise, applyQuicksilver Perfect Seal to end of new pipe and, using oil pump suction pipe installer(J-21882), tap the pipe in place with a hammer.

IMPORTANT: Oil internal parts liberally before installation.

1. Install pressure regulator valve and related parts.

2. Install drive gear in pump body.

3. Install idler gear in pump body with smooth side of gear toward pump cover opening.Align marks made in disassembly.

4. Fill gear cavity with engine oil.

5. Install pump cover and torque attaching bolts to 80 lb-in. (9 Nm).

Installation1. Install pump to rear main bearing.

2. Torque oil pump bolt to 65 lb-ft (88 Nm).

3. Install oil pan as outlined. The one-piece gasket for the oil pan may be reused if stillpliable and not cracked, torn, etc.


90-861329--1 MARCH 1999 Page 3A-37

Torsional Damper

Removal1. Support front of engine (if in boat) with overhead hoist.

2. Remove front mounting bracket and drive belt. Remove retaining bolt, if equipped.

3. Install tool J-6978-E to balancer and turn puller. Remove drive pulley, then removetorsional damper retaining bolt.

IMPORTANT: DO NOT use a universal claw type puller to remove torsional damper(in next step) as outside ring of torsional damper is bonded in rubber to the hub anduse of claw type puller may break the bond.

4. Remove torsional damper with torsional damper remover and installer.

72890

a

a - Torsional Damper Remover and Installer (J-6978-E)

InstallationIMPORTANT: The inertia weight section of torsional damper is assembled to the hubwith a rubber type material. The installation procedure (with proper tool) must befollowed or movement of the inertia weight on the hub will destroy the tuning of thetorsional damper.

1. Replace key in crankshaft if it is damaged.

2. Coat seal surface of torsional damper with engine oil.

NOTE: If a suitable torsional damper installer installation tool is not available, use a blockof wood as a driver. Be very careful not to cause pulley or weight to shift on their rubbermounts.

3. Install torsional damper on crankshaft, using torsional damper remover and installer asfollows:

a. Install appropriate end of threaded rod into crankshaft.

IMPORTANT: Be sure to install threaded rod in crankshaft at least 1/2 in. (13 mm) toprevent damage to threads.

b. Install plate, thrust bearing, washer and nut on rod.


Page 3A-38 90-861329--1 MARCH 1999

c. Install torsional damper on crankshaft by turning nut until it contacts.

74529

a

a - Torsional Damper Remover and Installer (J-23523-E)

d. Remove tool from crankshaft.

e. To prevent oil leakage, apply Quicksilver RTV sealant to torsional damper keyway.

f. Install torsional damper bolt. Torque to 70 lb-ft (95 Nm).

4. Install drive pulley(s). Torque bolts to 35 lb-ft (48 Nm).

5. Install and adjust drive belts.


90-861329--1 MARCH 1999 Page 3A-39

Crankcase Oil Seal

Replacing Oil Seal Without Removing Front Cover

REMOVAL

1. Remove torsional damper.

2. Pry seal out of cover from the front with a large screwdriver. Be careful not to distort frontcover or damage crankshaft.

INSTALLATION

IMPORTANT: Correct rotation oil seal must be used to prevent oil leak.

1. Apply Quicksilver Perfect Seal to seal retainer mating surface and apply grease to seallips.

2. Install new seal with open end of seal inward, using crankcase front cover seal installer.Drive seal in until it contacts. Do not use excessive force.

74531

a

b

a - Key In Crankshaftb - Lobe of Bore Clears Key

3. Reinstall torsional damper as outlined.


Page 3A-40 90-861329--1 MARCH 1999

Crankcase Front Cover

Removal1. Remove engine from boat if necessary to gain access to cover.

2. Remove torsional damper and oil pan.

3. Remove water circulating pump.

4. Remove crankcase front cover.

5. If damaged, drive oil seal out of front cover (from the rear) using a punch.

Cleaning and InspectionClean front cover in solvent and dry with compressed air. Clean old gasket material andsealer from mating surfaces on cover and cylinder block. Check gasket surface on frontcover for distortion, and fix if necessary. Surfaces must be clean and flat or oil leakage mayresult.

Installation1. Install oil seal in cover with lip of seal toward inside of engine, using crankcase front

cover seal installer. Support cover around seal area with appropriate tool as shown.

74530

a

a - Crankcase Front Cover Seal Installer (J-35468)

2. Coat both sides of front cover gasket with Quicksilver Perfect Seal and place in positionon engine.

3. Install front cover. Ensure holes in cover align with dowel pins in block. Torque frontcover attaching screws to 100 lb-in. (11 Nm).

4. Install oil pan and torsional damper as outlined.

5. Install water circulating pump.

6. Reinstall engine in boat.

7. Fill crankcase with engine oil.

CAUTIONEnsure that cooling water supply is available before starting the engine.

8. Start engine and check for water and oil leaks.


90-861329--1 MARCH 1999 Page 3A-41

Flywheel and Engine Coupler

Removal1. Remove engine from boat. Refer to SECTION 2 “Removal and Installation.”

2. Refer to “Flywheel Housing” description in this section and remove flywheel housing andrelated parts.

72318

b

c

a

a - Flywheel Housingb - Coverc - Press Mount Out with Press

3. Remove MCM coupler.

4. Remove flywheel.

72349

Alpha One Coupler

Inspection1. Inspect splines in coupler for wear.

2. Check flywheel ring gear for worn and missing teeth.


Page 3A-42 90-861329--1 MARCH 1999

Installation1. Clean mating surfaces of flywheel and crankshaft. Remove any burrs. Mating surfaces

must be clean bare metal.

2. Align dowel hole in flywheel with dowel in crankshaft.

3. Install flywheel.

4. Torque bolts to 75lb-ft (100Nm).

5. Check flywheel runout as follows:

a. Attach a dial indicator to engine block.

b. Take readings around outer edge of flywheel. Push in on flywheel to remove crank-shaft end play. Maximum runout - .008 in. (0.203 mm).

72353

ab

a - .008 in. (0.203 mm) Maximum Runoutb - Push Flywheel And Crankshaft Forward As Far As It Will Go When Taking

Reading

6. Insert three rubber bumpers in Alpha coupler before installation on flywheel.

72354

a

a - Rubber Bumper

7. Install drive coupler. If reusing screws, use Loctite 27131.

8. Torque bolts to 35 lb-ft (48 Nm).

9. Install flywheel housing and related parts. Torque bolts to 30 lb-ft (41 Nm).

10. Install flywheel housing cover. Torque bolts to 80 lb-in. (9 Nm).

11. Refer to SECTION 2 “Removal and Installation” and install engine.


90-861329--1 MARCH 1999 Page 3A-43

Rear Main Oil SealThe rear crankshaft oil seal can be replaced without removing the oil pan or rear mainbearing cap from engine.

Removal1. Remove seal by using a screwdriver to pry it out of retainer as shown.

72355

c

a b

a - Rear Sealb - Seal Retainerc - Slots (Three)

Cleaning and Inspection1. Clean crankshaft/seal running surface and seal retainer.

2. Clean gasket material from mating surfaces.

3. Inspect oil seal retainer for cracks or scored surface.

4. Inspect oil seal for worn, dry or torn rubber. Replace if necessary (refer to “Rear MainOil Seal” as outlined).

5. Inspect alignment pin for damage; replace if necessary.

IMPORTANT: Correct rotation oil seal must be used to prevent oil leak.

Installation1. Apply Quicksilver Perfect Seal to seal retainer mating surface. Apply grease to seal lips.

2. Install seal using rear main seal installer.

72356aa - Rear Main Seal Installer (J-26817-A)


Page 3A-44 90-861329--1 MARCH 1999

3. Coat seal lips with clean motor oil.

4. Install gasket and oil seal retainer with rear main seal.

5. Coat threads of oil seal retainer fasteners with Loctite Pipe Sealant with Teflon.

6. Install oil seal retainer fasteners and torque to 133 lb-in. (15 Nm).

7. Install oil pan fasteners. Torque 1/4-20 threaded fasteners to 80 lb-in. (9 Nm) and5/16-18 threaded fasteners to 165 lb-in. (19 Nm).

NOTE: The oil pan gasket may be re-used if it is still pliable and is not cracked, torn or other-wise damaged.

Main Bearings

IMPORTANT: Before removing main bearing caps or connecting rod caps, mark themfor reassembly in their original locations.

Main bearings are the precision insert type and do not use shims for adjustment. Ifclearances are found to be excessive, a new bearing, both upper and lower halves, will berequired. Service bearings are available in standard size and .001 in., .010 in. and .020 in.undersize.

Selective fitting of both rod and main bearing inserts is necessary in production in order toobtain close tolerances. For this reason you may find one-half of a standard insert with one-half of a .001 in. undersize insert which will decrease the clearance .0005 in. from using afull standard bearing.

When a production crankshaft cannot be precision fitted by this method, it then is ground.009 in. undersize on main journals only. A .009 in undersize bearing and .010 in. undersizebearing may be used for precision fitting in same manner as previously described. Anyengine fitted with a .009 in. undersize crankshaft will be identified by the following markings:

• “.009” will be stamped on crankshaft counterweight forward of center main journal.

• No. “9” will be stamped on block at left front oil pan rail.

IMPORTANT: If crankshaft has an undersize journal and a new bearing is required,journal must be reconditioned to accept a .010 or .020 in. undersize bearing as .009in. undersize bearings are not available for service.

InspectionIn general, the lower half of the bearing (except No. 1 bearing) shows greater wear and moredistress from fatigue. If, upon inspection, the lower half is suitable for use, it can be assumedthat the upper half is also satisfactory. If the lower half shows evidence of wear or damage,both upper and lower halves should be replaced. Never replace one half without replacingthe other half.


90-861329--1 MARCH 1999 Page 3A-45

Checking ClearancesTo obtain accurate measurements while using Plastigage, or its equivalent, engine must beout of the boat and upside down so crankshaft will rest on the upper bearings and total clear-ance can be measured between lower bearing and journal.

To ensure the proper seating of the crankshaft, all bearing cap bolts should be at their speci-fied torque. In addition, prior to checking fit of bearings, the surface of the crankshaft journaland bearing should be wiped clean of oil.

1. With the oil pan and oil pump removed, remove bearing cap and wipe oil from journaland bearing cap to be inspected.

2. Place a piece of gauging plastic the full width of the bearing (parallel to the crankshaft)on the journal as shown.

72558

a

b

a - Gauging Plasticb - Journal

3. Install the bearing cap and evenly torque the retaining bolts to specifications. Bearingcap MUST be torqued to specification in order to ensure proper reading. Variations intorque affect the compression of the plastic gauge.

IMPORTANT: Do not rotate the crankshaft while the gauging plastic is between thebearing and journal.

4. Remove bearing cap. The flattened gauging plastic will be found adhering to either thebearing cap or journal.


Page 3A-46 90-861329--1 MARCH 1999

5. On the edge of the gauging plastic envelope there is a graduated scale which is corre-lated in thousandths of an inch. Without removing the gauging plastic, measure its com-pressed width (at the widest point) with the graduations on the gauging plastic envelopeas shown.

72358

a b

a - Compressed Gauging Plasticb - Graduated Scale

NOTE: Normally main bearing journals wear evenly and are not out of round. However, ifa bearing is being fitted to an out-of-round journal (.001 in. max.), be sure to fit to themaximum diameter of the journal. If the bearing is fitted to the minimum diameter and thejournal is out of round .001 in., interference between the bearing and journal will result inrapid bearing failure. If the flattened gauging plastic tapers toward the middle or ends, thereis a difference in clearance indicating taper, low spot or other irregularity of the bearing orjournal. Be sure to measure the journal with a micrometer if the flattened gauging plasticindicates more than .001 in. difference.

6. If the bearing clearance is within specifications, the bearing insert is satisfactory. If theclearance is not within specifications, replace the insert. Always replace both upper andlower inserts as a unit.

7. A standard, or .001 in., undersize bearing may produce the proper clearance. If not, itwill be necessary to regrind the crankshaft journal for use with the next undersizebearing.

8. After selecting new bearing, recheck clearance.

9. Proceed to the next bearing. After all bearings have been checked, rotate the crankshaftto see that there is no excessive drag. When checking No. 1 main bearing, loosen acces-sory drive belts so as to prevent tapered reading with plastic gauge.

Main Bearing Replacement1. Remove and inspect crankshaft.

2. Remove main bearings from cylinder block and main bearing caps.

3. Coat bearing surfaces of new, correct-size, main bearing with oil and install in cylinderblock and main bearing caps. Check clearance.

4. Install crankshaft.

5. Torque all main bearing caps, EXCEPT THE REAR MAIN CAP, to 75 lb-ft (102 Nm).

6. Torque rear main bearing cap to 10-12 lb-ft (14-16 Nm); then tap end of crankshaft, firstrearward then forward with a lead hammer. This will line up rear main bearing and crank-shaft thrust surfaces. Torque rear main bearing cap to 75 lb-ft (102 Nm).


90-861329--1 MARCH 1999 Page 3A-47

Connecting Rod BearingsConnecting rod bearings are of the precision insert type and do not use shims for adjust-ment. DO NOT FILE RODS OR ROD CAPS. If clearances are found to be excessive, a newbearing will be required. Service bearings are available in standard size and .001 in. and.002 in. undersize for use with new and used standard size crankshafts, and in .010 in. and.020 in. undersize for use with reconditioned crankshafts.

On removing a connecting rod cap, it is possible to find a .010 in. undersize bearing. Theseare used in manufacturing for selective fitting.

Inspection and ReplacementIMPORTANT: Before you remove the connecting rod cap, mark the side of the rod andcap with the cylinder number to assure matched reassembly of rod and cap.

1. Remove connecting rod cap and bearing.

2. Inspect bearing for evidence of wear or damage. Defective bearings should not beinstalled. Typical bearing failures are shown under “General.”

3. Wipe bearings and crankshaft clean of oil.

4. Measure crankpin for out-of-round of taper with a micrometer. If not within specifica-tions, replace or recondition crankshaft. If within specifications and new bearing is to beinstalled, measure maximum diameter of crankpin to determine new bearing sizerequired.

5. If within specifications, measure new or used bearing clearances with gauging plastic.

IMPORTANT: If bearing is fitted to out-of-round crankpin, br sure to fit maximumdiameter of crankpin. If bearing is fitted to minimum diameter, and crankpin isout-of-round .001 (0.02 mm), interference between bearing and crankpin will resultin rapid bearing failure.

a. Place a piece of gauging plastic the full width of crankpin (parallel to crankshaft).

b. Install bearing connecting rod and cap.

c. Place a piece of gauging plastic the length of the bearing (parallel to the crankshaft)on the crankpin or bearing surface as shown. Position the gauging plastic in themiddle of the bearing shell. Bearings are eccentric and false readings could occurif placed elsewhere.

72361

a

a - Gauging Plastic

d. Install the bearing in the connecting rod and cap.


Page 3A-48 90-861329--1 MARCH 1999

e. Install the bearing cap and torque nuts to 45 lb-ft (61 Nm).

IMPORTANT: Do not turn the crankshaft with the gauging plastic installed.

f. Remove the bearing cap and using the scale on the gauging plastic envelope, mea-sure the gauging plastic width at the widest point as shown.

72362

6. If the clearance exceeds specifications, select a new, correct size bearing and measurethe clearance.

Be sure to check what size bearing is being removed in order to determine proper replace-ment size bearing. If clearance cannot be brought to within specifications, the crankpin willhave to be ground undersize. If the crankpin is already at maximum undersize, replacecrankshaft.

7. Coat the bearing surface with oil, install the rod cap and torque nuts to 45 lb-ft (61 Nm).

8. When all connecting rod bearings have been installed, tap each rod lightly (parallel tothe crankpin) to make sure they have clearance.

9. Measure all connecting rod side clearances between connecting rod caps as shown -.006-.014 in. (0.16-0.35 mm).

72891

a

a - Take Measurement Here


90-861329--1 MARCH 1999 Page 3A-49

Connecting Rod/Piston AssemblyRemoval

1. With oil pan, oil pump and cylinder head removed, use a ridge reamer to remove anyridge and/or deposits from upper end of cylinder bore.

IMPORTANT: Before ridge and/or deposits are removed, turn crankshaft until pistonis at bottom of stroke and place a cloth on top of piston to collect cuttings. After ridgeand/or deposits are removed, turn crankshaft until piston is at top of stroke, thenremove cloth and cuttings.

2. Inspect and mark connecting rods and bearing caps.

3. Remove connecting rod cap and install connecting rod bolt guide (3/8-24) on bolts. Pushconnecting rod and piston assembly out of top of cylinder block.

NOTE: It will be necessary to turn crankshaft slightly to disconnect and remove some con-necting rod and piston assemblies.

72892

a

a - Connecting Rod Bolt Guide (3/8-24) (J-5239)

Disassembly1. Disassemble piston from connecting rod using piston pin remover as shown.

72365

a

b

d

c

e

a - Piston Pin Remover (J-24086-B)b - Arched Basec - Pistond - Connecting Rode - Rod Support

2. Position connecting rod on tool rod support with rod support inserted betweenconnecting rod end and piston. Align piston pin with hole located in top of arched base.

3. Insert pin remover through hole (located in top of arched base) and into piston pin hole.Press on pin remover to remove piston pin.


Page 3A-50 90-861329--1 MARCH 1999

Cleaning and Inspection

CONNECTING RODS

1. Wash connecting rods in cleaning solvent and dry with compressed air.

2. Check for twisted and bent rods and inspect for nicks and cracks. Replace damagedconnecting rods.

PISTONS

NOTE: Cylinder bore and taper must be within specifications before pistons can be consid-ered for reuse.

1. Clean varnish from piston skirts with a cleaning solvent. DO NOT WIRE BRUSH ANYPART OF PISTON. Clean ring grooves with a groove cleaner and make sure oil ringholes are clean.

2. Inspect piston for cracked ring lands, skirts and pin bosses, wavy worn ring lands,scuffed or damaged skirts and eroded areas at top of piston. Replace pistons that aredamaged or show signs of excessive wear.

3. Inspect grooves for nicks and burrs that might cause rings to hang up.

4. Measure piston skirt (across centerline of piston pin) and check clearance as outlinedunder “Cylinder Block.”

5. Slip outer surface of a new top and second compression ring into respective piston ringgroove and roll ring entirely around the groove to ensure that ring is free as shown. Ifbinding occurs at any point, determine cause. If caused by ring groove, remove by dres-sing with a fine cut file. If binding is caused by a distorted ring, recheck with another ring.

72894

6. Proper clearance of piston ring in its piston ring groove is very important to provideproper ring action and reduce wear. When fitting new rings, clearances between ringand groove surfaces should be measured. See “Specifications.”

72895


90-861329--1 MARCH 1999 Page 3A-51

PISTON PINS

1. Piston pin clearance is designed to maintain adequate clearance under all engineoperating conditions. Because of this, piston and piston pin are a matched set and notserviced separately.

2. Inspect piston pin bores and piston pins for wear. Piston pin bores and piston pins mustbe free of varnish and scuffing when measured. Measure piston pin with a micrometerand piston pin bore with a dial bore gauge or inside micrometer. If clearance is in excessof the .001 in. (0.02 mm) wear limit, replace piston and piston pin assembly.

Reassembly

PISTONS AND PISTON PINS

IMPORTANT: When reassembling pistons and connecting rods, the following mustbe kept in mind.

• Piston and pin are machine fitted to each other and must remain together as amatched set. Do not intermix pistons and pins.

• If original pistons and/or connecting rods are being used, be sure to assemblepistons and connecting rods so they can be reinstalled in same cylinder fromwhich they were removed.

• Connecting rod bearing tangs are always toward outside of cylinder block.

72368

a

a - Rod Bearing Tangs

• Notch on piston must be positioned toward the front of the engine.

72896

a

a - Notch


Page 3A-52 90-861329--1 MARCH 1999

1. Assemble piston to connecting rod using piston pin remover as shown. Follow instruc-tions supplied with tool.

72371

a

a - Piston Pin Remover (J-24086-B)

2. Once assembled, check piston for freedom of movement (back and forth and up anddown) on connecting rod. Piston should move freely in all directions. If it does not, pistonpin bore is tight and piston/pin assembly must be replaced.

3. If a new connecting rod has been installed, mark connecting rod and cap (on side of rodand cap with slots for connecting rod bearing tangs) with cylinder number in which it willbe installed.

PISTON RINGS

All compression rings are marked on upper side of ring. When installing compression rings,make sure that marked side is toward top of piston. The top ring is treated with molybdenumfor maximum life. Oil control rings are a three piece type, consisting of 2 segments (rails)and a spacer.

Oil control rings are a three-piece type, consisting of two rings and a spacer.

1. Select rings comparable in size to cylinder bore and piston size.

2. Slip compression ring in cylinder bore, then press ring down into cylinder bore about 1/4in. (6 mm) (below ring travel). Be sure that ring is square with cylinder wall.

3. Measure gap between ends of ring with a feeler gauge as shown.

72372

4. If gap between ends of ring is below specifications, remove ring and try another for fit.

5. Fit each compression ring to cylinder in which it is going to be used.


90-861329--1 MARCH 1999 Page 3A-53

6. Clean and inspect pistons, if not previously done.

7. Install piston rings as follows:

a. Install oil ring spacer in groove and insert anti- rotation tang in oil hole.

b. Hold spacer ends butted and install lower steel oil ring rail with gap properly located.

c. Install upper steel oil ring rail with gap properly located.

d. Flex the oil ring assembly to make sure ring is free. If binding occurs at any point,the cause should be determined and, if caused by ring groove, removed by dressinggroove with a fine cut file. If binding is caused by a distorted ring, use a new ring.

IMPORTANT: Use piston ring expander (91-24697) for compression ring installation.

e. Install lower compression ring with marked side up, using ring expander.

f. Install top compression ring with marked side up, using ring expander.

InstallationIMPORTANT: Cylinder bores must be clean before piston installation. Clean with alight honing, as necessary. Then clean with hot water and detergent wash. Aftercleaning, swab bores several times with light engine oil and clean cloth, then wipewith a clean dry cloth.

1. Lubricate connecting rod bearings and install in rods and rod caps.

2. Lightly coat pistons, rings and cylinder walls with light engine oil.

3. With bearing caps removed, install connecting rod bolt guide (3/8-24) (J-5239) onconnecting rod bolts.

IMPORTANT: Be sure ring gaps are properly positioned as shown.

72373

a

b

b

c d

e f g

Ring Gap Locationa - Oil Ring Spacer Gap (Tang In Hole Or Slot Within Arc)b - Oil Ring Gapsc - 2nd Compression Ring Gapd - Top Compression Ring Gape - Port Sidef - Engine Frontg - Starboard Side

4. Install each connecting rod and piston assembly in its respective bore.

a. Install with connecting rod bearing tangs toward outside of cylinder block.

b. Use piston ring compressor to compress rings.

c. Guide connecting rod into place on crankshaft journal with connecting rod bolt guide.


Page 3A-54 90-861329--1 MARCH 1999

d. Use a hammer handle with light blows to install piston into bore.

e. Hold ring compressor firmly against cylinder block until all piston rings have enteredcylinder bore.

IMPORTANT: Be sure to install new pistons in same cylinders for which they werefitted, and used pistons in same cylinder from which they were removed. Eachconnecting rod and bearing cap should be marked, beginning at front of engine.Numbers on connecting rod and bearing cap must be on same side when installedin cylinder bore. If a connecting rod is ever transposed from one block or cylinder toanother, new bearings should be fitted and connecting rod should be numbered tocorrespond with new cylinder number.

72898

a

a - Piston Ring Compressor (J-8037)

5. Remove connecting rod bolt guide.

6. Install bearing caps and torque nuts to 45 lb-ft (27 Nm).

7. Check connecting rod side clearance as previously described.

NOTE: If bearing replacement is required, refer to “Connecting Rod Bearings.”

8. Install as previously outlined:

a. Oil pump.

b. Dipstick and oil pan.

c. Cylinder heads.

d. Intake manifold.

e. Distributor.

9. Torque rocker arm nuts to 20 lb-ft (27 Nm).

10. Install rocker arm cover and torque to 40 lb-in (4.5 Nm)

11. Fill crankcase with oil. Refer to SECTION 1B “Maintenance.”


90-861329--1 MARCH 1999 Page 3A-55

CrankshaftRemoval

1. Remove engine from boat.

2. Drain crankcase oil.

3. Remove as outlined:

a. Starter.

b. Flywheel housing.

c. Drive coupler and flywheel.

d. Belts.

e. Water pump.

f. Crankshaft pulley and torsional damper.

g. Spark plugs.

h. Oil pan and dipstick tube.

i. Oil pump.

j. Timing chain cover.

4. Turn crankshaft to align timing mark with camshaft mark.

5. Remove camshaft sprocket.

6. Remove rear main seal and retainer.

7. Ensure all bearing caps (main and connecting rods) are marked so they can be rein-stalled in their original locations.

8. Remove connecting rod bearing caps, then push piston and rod assemblies towardheads.

9. Remove main bearing caps and carefully lift crankshaft out of cylinder block.

10. Remove crankshaft gear as shown.

74476

11. If new main and/or connecting rod bearings are to be installed, remove main bearinginserts from cylinder block and bearing caps, and/or connecting rod bearing inserts fromconnecting rod and caps. Install new bearings following procedures outlined.


Page 3A-56 90-861329--1 MARCH 1999

Cleaning and Inspection1. Wash crankshaft in solvent and dry with compressed air.

2. Measure main bearing journals and crankpin dimensions with a micrometer forout-of-round, taper or undersize (see “Specifications”).

3. Check crankshaft for runout (by supporting at front and rear main bearings journals inV-blocks) and check at front and rear intermediate journals with a dial indicator (see“Specifications”).

4. Replace or recondition crankshaft if not within specifications.

Installation1. If a new crankshaft is being installed, remove timing sprocket from old crankshaft and

reinstall on new crankshaft as outlined.

IMPORTANT: Be sure that all bearings and crankshaft journals are clean.

2. Install main bearings in engine block as shown.

72359

ab

c

Main Bearing Insertsa - Lower Bearing Insertb - Upper Bearing Insertc - Oil Groove

3. Carefully lower crankshaft into place. Be careful not to damage bearing surface.

4. Check clearance of each main bearing, following procedure outlined under “Main Bear-ings.” If bearing clearances are satisfactory, apply engine oil to journals and bearings.

5. Install main bearing caps. Torque bolts to 75 lb-ft (102 Nm). When tightening rear mainbearing cap, follow procedure outlined under “Main Bearings.”

6. Check crankshaft end play as previously outlined.

7. Install rear main seal retainer and seal. Torque fasteners to 133 lb-in. (15 Nm).

8. Check clearance for each connecting rod bearing, following procedure under “Connect-ing Rod Bearings.” If bearing clearances are satisfactory, apply engine oil to journals andbearings.

9. Install rod caps and torque nuts to 45 lb-ft (61 Nm).

10. Turn crankshaft so mark on timing sprocket is facing camshaft.


90-861329--1 MARCH 1999 Page 3A-57

11. Install as outlined:

a. Timing chain and sprocket on camshaft - align marks with crankshaft.

b. Timing chain cover.

c. Oil pump.

d. Dipstick tube and oil pan.

e. Spark plugs.

f. Torsional damper and crankshaft pulley.

g. Water pump.

h. Belts.

i. Flywheel and drive coupler.

j. Flywheel housing.

k. Starter.

12. Install new oil filter. Fill crankcase with oil.

Crankshaft Sprocket

Removal1. Remove torsional damper and crankcase front cover as previously outlined.

2. Remove camshaft timing chain as outlined, and using crankshaft gear and sprocketpuller (J-5825-A), remove crankshaft sprocket.

Installation1. Using crankshaft gear and sprocket installer, as shown, install sprocket on crankshaft.

72377

a

a - Crankshaft Gear and Sprocket Installer (J-5590)

2. Install timing chain as outlined.

3. Install crankcase cover and torsional damper as outlined.


Page 3A-58 90-861329--1 MARCH 1999

Camshaft

Measuring Lobe LiftNOTE: Procedure is similar to checking valve timing. If improper valve operation is indi-cated, measure lift of each push rod in consecutive order and record readings.

1. Remove valve mechanism as previously outlined.

2. Position indicator with ball socket adaptor tool on push rod. Be sure that push rod is inlifter socket.

72907

a

a - Ball Socket Adaptor Tool (J-8520-1)

3. Rotate crankshaft torsional damper slowly in direction of rotation until lifter is on heel ofcam lobe. At this point, push rod will be in its lowest position.

4. Set dial indicator on zero, then rotate balancer slowly (or attach an auxiliary starterswitch and “bump” engine over) until push rod is in fully raised position.

5. Compare total lift, recorded from dial indicator, with “Specifications.”

6. Continue to rotate engine until indicator reads zero. This will be a check on accuracy oforiginal indicator reading.

7. If camshaft readings for all lobes are within specifications, remove dial indicator assem-bly.

8. Install rocker arm and push rod. Torque nuts to 20 lb-ft (27 Nm).

Removal1. Remove valve lifters as previously outlined.

2. Remove crankcase front cover as previously outlined.

3. Remove fuel pump.

4. Align timing gear marks, then remove the two camshaft thrust plate screws by workingthrough holes in camshaft gear.


90-861329--1 MARCH 1999 Page 3A-59

5. Pull camshaft and gear assembly out through front of block.

IMPORTANT: Support camshaft carefully when removing to protect camshaft bear-ings.

74438

a b

a - Timing Marksb - Screw Access Holes

Inspection1. Measure camshaft bearing journals with a micrometer for out-of-round condition. If

journals exceed .001 in. (0.02 mm) out-of-round, camshaft should be replaced.

2. Also check camshaft for alignment with V-blocks and dial indicator which indicates exactamount camshaft is out of true. If dial indicator reads more than .002 in. (0.05 mm)camshaft should be replaced.

72909

Checking Camshaft Alignment

3. Inspect camshaft gear and thrust plate for wear or damage. Measure camshaft end play.001 - .005 in. (0.03-0.1 mm).

74439

d

a

bc

a - Feeler Gaugeb - Camshaft Gearc - Camshaft Thrust Plated - Take Measurement Here


Page 3A-60 90-861329--1 MARCH 1999

Camshaft Gear Replacement1. If inspection indicates that camshaft, gear or thrust plate should be replaced, remove

gear from camshaft.

2. Place camshaft through gear remover, place end of remover on table of a press shaftout of gear.

CAUTIONPosition thrust plate so that woodruff key in shaft does not damage plate when shaftis pressed out of gear. Also support hub of gear, or gear will be seriously damaged.

74477

b

a

c

a - Camshaft Gearb - Support Sleevec - Camshaft

Installation1. Install camshaft and gear assembly in engine block. Be careful not to damage camshaft

bearings or camshaft.

74438

a b

a - Timing Marksb - Screw Access Holes

2. Turn crankshaft and camshaft so the timing marks on gear teeth will line up. Pushcamshaft thrust plate to block screws and torque to specifications.


90-861329--1 MARCH 1999 Page 3A-61

3. Check camshaft and crankshaft gear run-out with a dial indicator. Camshaft gear run-outshould not exceed .004 in. (0.1 mm) and crankshaft gear run-out should not exceed .003in. (0.07 mm).

74440

Checking Timing Gear Run-Out

4. If gear run-out is excessive, remove gear and clean burrs from shaft or replace gear.

5. Check backlash between timing gear teeth with a dial indicator. Backlash should not beless than .004 in. (0.010 mm) or more than .006 in. (0.15 mm).

74441

Checking Timing Gear Backlash

6. Install fuel pump.

7. Install front crankcase cover.

8. Pour GM engine oil supplement or light engine oil over camshaft lobes and install valvelifters.


Page 3A-62 90-861329--1 MARCH 1999

Camshaft Bearings

RemovalCamshaft bearings can be replaced while engine is disassembled for overhaul or withoutcomplete disassembly. To replace bearings without complete disassembly, remove cam-shaft and crankshaft, leaving cylinder heads attached and pistons in place. Before removingcrankshaft, fasten connecting rods against sides of engine so that they will not interferewhile replacing camshaft bearings.

1. With camshaft and crankshaft removed, drive camshaft rear plug from cylinder block.

NOTE: This procedure is based on removal of bearings from center of engine first, thusrequiring a minimum amount of turns to remove all bearings.

2. Using camshaft bearing remover and installer set (J-6098-01) (with nut and thrustwasher installed to end of threads), position pilot in front camshaft bearing and installpuller screw through pilot.

3. Install tool with shoulder toward bearing. Be sure a sufficient amount of threads areengaged.

4. Using two wrenches, hold puller screw while turning nut. When bearing has been pulledfrom bore, remove tool and bearing from puller screw.

74478

5. Remove remaining bearings (except front and rear) in same manner. It will be necessaryto position pilot in rear camshaft bearing to remove rear intermediate bearing.

74479

6. Assemble driver on driver handle and remove front and rear camshaft bearings bydriving toward center of cylinder block.


90-861329--1 MARCH 1999 Page 3A-63

InspectionClean camshaft bearing bores in cylinder block with solvent and blow out with compressedair. Be sure grooves and drilled oil passages are clean.

Installation

CAUTIONOil holes in bearings must line up with oil holes in cylinder block. Oil hole is on topside of bearing shell and cannot be seen during installation, so first align bearingshell oil hole with oil hole in bore and mark opposite side of bearing and block atbore to easily position oil hole during installation.

IMPORTANT: Front bearing must be driven approximately .125 in. (3 mm) behind theblock face to uncover oil hole to timing gear oil nozzle.

IMPORTANT: All camshaft bearings are not the same. Be sure to install bearings inproper locations (Indicated by bearing manufacturer) and to position bearings asfollows (directional references are in reference to engine in its normal operatingposition):

Lubricate outer surface of new camshaft bearings with engine oil to ease installation.

1. Installing intermediate and center bearings:

a. Install nut and thrust washer all the way onto puller screw, then position pilot in frontcamshaft bearing bore and insert screw through pilot.

b. Index center camshaft bearing, then position appropriate size remover and installertool in bearing and thread puller screw into tool. Be sure at least 1/2 in. (13 mm) ofthreads are engaged.

74478

Pulling Cam Bearing From Bore

c. Using two wrenches, hold puller screw and turn nut until bearing has been pulled intoposition. Remove the remover and installer tool and ensure that oil hole(s) in bearingis positioned correctly.

d. Install intermediate bearings in same manner. Be sure to index bearings correctly.It will be necessary to position pilot in rear camshaft bearing bore to install rear inter-mediate bearing.

2. Installing front and rear bearings:

a. Install appropriate size remover and installer tool on drive handle.


Page 3A-64 90-861329--1 MARCH 1999

b. Index front bearing (as explained in “Important” above), and drive it into position withtool. Check position of oil hole(s) in bearing to ensure bearing is positioned correctly.

74479

Removal And Installation Camshaft Bearingsa - Installation Toolb - Camshaft Bearing

c. Install rear bearing in same manner. Be sure to index bearing correctly.

3. Install a new camshaft rear plug.

IMPORTANT: Plug must be installed flush to 1/32 in. (0.8 mm) deep and must be paral-lel with rear surface of cylinder block.

4. Install crankshaft and camshaft as previously outlined.

Cylinder Block

Cleaning and Inspection1. Remove all engine components as previously outlined.

2. Wash cylinder block thoroughly in cleaning solvent and clean all gasket surfaces.

3. Remove oil gallery plugs and clean all oil passages.

4. Remove expansion plugs.

NOTE: These plugs may be removed with a sharp punch or they may be drilled and priedout.

5. Clean and inspect water passages in cylinder block.

6. Inspect cylinder block for cracks in cylinder walls, water jacket valve lifter bores and mainbearing webs.


90-861329--1 MARCH 1999 Page 3A-65

7. Measure cylinder bores to ensure they meet specifications.

CAUTIONMeasure cylinder walls for taper, out-of-round or excessive ridge at top of ringtravel. This should be done with a dial indicator or inside micrometer. Carefullywork gauge up and down cylinder to determine taper and turn it to different pointsaround cylinder wall to determine out-of-round condition. If cylinders exceedspecifications, boring and/or honing will be necessary.

72385

a

b

a

b

Cylinder Measurementa - At right angle to centerline of engineb - Parallel to centerline of engine

“Out-of-Round” = Difference between “A” and “B”“Taper” =Difference between measurement “A” at top of cylinder bore and “A” measurementat bottom of cylinder bore

72386

Measuring Cylinder Bore With Snap Gauge

72387

Measuring Cylinder Bore With Dial Indicator


Page 3A-66 90-861329--1 MARCH 1999

8. Check cylinder head gasket surfaces for warp with a machinist’s straight-edge and afeeler gauge, as shown. Take measurements diagonally across surfaces (both ways)and straight down center. If surfaces are warped more than .003 in. (0.07 mm) in a 6 in.area or .007 in. (0.2 mm) overall, block must be resurfaced by an automotive machineshop.

72910a

b

a - Machinist’s Straight-Edgeb - Feeler Gauge

CYLINDER CONDITIONING

1. Performance of the following operation depends upon engine condition at time of repair.

2. If cylinder block inspection indicates that block is suitable for continued use (except forout-of-round or tapered cylinders), they can be conditioned by honing or boring.

3. If cylinders have less than .005 in. (0.127 mm) taper or wear, they can be conditionedwith a hone and fitted with high limit standard size piston. A cylinder bore of more than.005 in. wear or taper may not clean up entirely when fitted to a high limit piston. Toentirely clean up the bore, it will be necessary to bore for an oversize piston. If more than.005 in. taper or wear, bore and hone to smallest oversize that will permit completeresurfacing of all cylinders.

4. When pistons are being fitted and honing is not necessary, cylinder bores may becleaned with a hot water and detergent wash. After cleaning, swab cylinder boresseveral times with light engine oil and a clean cloth, then wipe with a clean dry cloth.

CYLINDER BORING

1. Before using any type boring bar, file off top of cylinder block to remove dirt or burrs. Thisis very important to prevent boring bar tilt, resulting in the bored cylinder wall not beingat right angles to crankshaft.

2. Measure piston to be fitted with a micrometer, measuring at center of piston skirt andat right angles to piston pin. Bore cylinder to same diameter as piston and hone to givespecified clearance.

NOTE: Hone cylinders as outlined under “Cylinder Honing” and “Piston Selection,”following.

3. Carefully observe instructions furnished by manufacturer of equipment being used.


90-861329--1 MARCH 1999 Page 3A-67

CYLINDER HONING

1. Follow hone manufacturer’s recommendations for use of hone and cleaning and lubrica-tion during honing.

2. Occasionally, during the honing operation, thoroughly clean cylinder bore and checkpiston for correct fit in cylinder.

3. When finish-honing a cylinder bore to fit a piston, move hone up and down at a sufficientspeed to obtain very fine uniform surface finish marks in a crosshatch pattern of approxi-mately 30 degrees to cylinder bore. Finish marks should be clean but not sharp, freefrom imbedded particles and torn or folded metal.

4. Permanently mark piston (for cylinder to which it has been fitted) and proceed to honecylinders and fit remaining pistons.

IMPORTANT: Handle pistons with care and do not attempt to force them through cyl-inder until cylinder is honed to correct size, as this type piston can be distorted bycareless handling.

5. Thoroughly clean cylinder bores with hot water and detergent. Scrub well with a stiffbristle brush and rinse thoroughly with hot water. It is extremely essential that a goodcleaning operation be performed. If any abrasive material remains in cylinder bores, itwill rapidly wear new rings and cylinder bores in addition to bearings lubricated by thecontaminated oil. Swab bores several times with light engine oil on a clean cloth, thenwipe with a clean dry cloth. Cylinder should not be cleaned with kerosene or gasoline.Clean remainder of cylinder block to remove excess material spread during honingoperation.


Page 3A-68 90-861329--1 MARCH 1999

PISTON SELECTION

1. Check used piston to cylinder bore clearance as follows:

a. Measure cylinder bore diameter with a snap gauge 2-1/2 in. (64 mm) from top of cyl-inder bore as follows.

72386

b. Measure piston diameter at skirt across center line of piston pin as shown.

72911

c. Subtract piston diameter from cylinder bore diameter to determine piston-to-boreclearance.

d. Determine if piston-to-bore clearance is in acceptable range shown in “Specifica-tions.”

2. If used piston is not satisfactory, determine if a new piston can be selected to fit cylinderbore within acceptable range.

3. If cylinder bore must be reconditioned, measure new piston diameter (across centerlineof piston pin), then hone cylinder bore to correct clearance (preferable range).

4. Mark piston to identify cylinder for which it was fitted.


90-861329--1 MARCH 1999 Page 3A-69

Oil Filter By-Pass Valve

Inspection and/or ReplacementWith oil filter removed, check spring and fiber valve for operation. Inspect for a cracked orbroken valve. If replacement is necessary, pry valve out with screwdriver. Install and seata new valve by tapping in place with a 9/16 in. thin wall deep socket.

Refer to “Engine Parts List” when ordering parts for oil filter by-pass valve.

1. Remove oil filter from cylinder block and remove by-pass valve.

2. Clean by-pass valve in solvent and blow dry with compressed air.

3. Inspect fiber valve for cracks or other damage. Check that valve fits tightly against itsseat. Push valve down and release it. Valve should return freely to its seat. If valveoperation is questionable, by-pass valve should be replaced.

72912

a

Typical By-Pass Valvea - Fiber Valve (Ensure Valve Fits Tightly Against the Seal)

4. Wipe out valve chamber in cylinder block to remove any foreign material.

5. Install by-pass valve or cylinder block adaptor to engine block.

6. Lubricate oil filter rubber seal and install hand-tight only.


Page 3A-70 90-861329--1 MARCH 1999



90-861329--1 MARCH 1999 Page 3A-71



Page 3A-72 90-861329--1 MARCH 1999


4A

STARTING SYSTEMSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 4A-1

ELECTRICAL SYSTEMSection 4A - Starting System

Table of Contents

Identification 4A-2. . . . . . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 4A-2. . . . . . . . . . . . Battery 4A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Battery Cable Recommendations 4A-3. . . . . Starting System Components 4A-4. . . . . . . . . . . Replacement Parts Warning 4A-5. . . . . . . . . . . .

Maintenance 4A-5. . . . . . . . . . . . . . . . . . . . . . . Storage 4A-6. . . . . . . . . . . . . . . . . . . . . . . . . . . Testing 4A-7. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Positive Current Flow 4A-8. . . . . . . . . . . . . . . . . . Charging Guide 4A-9. . . . . . . . . . . . . . . . . . . . . . .

12 Volt Battery Recommended Rate* and Time for Fully Discharged Condition 4A-9. . . . . . . . . . . . . . . . . . . . . . . . .

Slave Solenoid Identification 4A-10. . . . . . . . . . . Types 4A-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard Type Slave Solenoid 4A-10. . . . . . Switch Type Slave Solenoid 4A-10. . . . . . . . . Testing/Replacement 4A-11. . . . . . . . . . . . . . .

Solenoid Switch 4A-11. . . . . . . . . . . . . . . . . . . . . . Periodic Inspection 4A-11. . . . . . . . . . . . . . . . . . . PG260 Starter Motor 4A-12. . . . . . . . . . . . . . . . . .

PG260 Specifications 4A-12. . . . . . . . . . . . . . Torque Specification 4A-12. . . . . . . . . . . . . . . Description 4A-12. . . . . . . . . . . . . . . . . . . . . . . PG260 Exploded View 4A-13. . . . . . . . . . . . .

Starter Motor Repair 4A-14. . . . . . . . . . . . . . . . . . Removal 4A-14. . . . . . . . . . . . . . . . . . . . . . . . . Disassembly 4A-14. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 4A-18. . . . . . . . . . . . Armature Tests 4A-19. . . . . . . . . . . . . . . . . . . . Armature Bearing (Commutator End) 4A-20. Gear Bearing 4A-20. . . . . . . . . . . . . . . . . . . . . Shaft Assembly Bearing 4A-21. . . . . . . . . . . . Drive End Housing Bearing 4A-21. . . . . . . . . Brushes and Brush Holder 4A-22. . . . . . . . . . Reassembly 4A-24. . . . . . . . . . . . . . . . . . . . . .

Starter Solenoid 4A-28. . . . . . . . . . . . . . . . . . . . . . Testing/Replacement 4A-28. . . . . . . . . . . . . . . Installation 4A-30. . . . . . . . . . . . . . . . . . . . . . . .

PG260F1 Starter Motor 4A-31. . . . . . . . . . . . . . . PG260F1 Specifications 4A-31. . . . . . . . . . . . Torque Specifications 4A-31. . . . . . . . . . . . . . Lubricants/Sealants 4A-31. . . . . . . . . . . . . . . . Description 4A-31. . . . . . . . . . . . . . . . . . . . . . . Exploded View 4A-32. . . . . . . . . . . . . . . . . . . .

Starter Motor Repair 4A-33. . . . . . . . . . . . . . . . . . Removal 4A-33. . . . . . . . . . . . . . . . . . . . . . . . . Disassembly 4A-33. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 4A-37. . . . . . . . . . . . Armature Tests 4A-37. . . . . . . . . . . . . . . . . . . . Reassembly 4A-38. . . . . . . . . . . . . . . . . . . . . . Starter Solenoid 4A-42. . . . . . . . . . . . . . . . . . . Installation 4A-44. . . . . . . . . . . . . . . . . . . . . . . .

STARTING SYSTEM SERVICE MANUAL NUMBER 26

Page 4A-2 90-861329--1 MARCH 1999

Identification

The starter identification number is located as shown.

72059

a

Delco PG 260 Starter Motora - Starter Identification Number

75820

Delco PG260F1 Starter Motor

NOTE: The RP long block, S/N 0L097000 and above, has 3 starter motor mounting holesin the cylinder block. The RK long block, S/N 0L096999 and below, has 2 starter motormounting holes in the cylinder block.

Replacement Parts Warning

WARNINGElectrical, ignition and fuel system components on your MerCruiser are designedand manufactured to comply with U.S. Coast Guard Rules and Regulations tominimize risks of fire and explosion.

WARNINGUse of replacement electrical, ignition or fuel system components, which do notcomply with these rules and regulations, could result in a fire or explosion hazardand should be avoided.


90-861329--1 MARCH 1999 Page 4A-3

Battery

Battery Cold Cranking Amperage

3.0L 375 cca, 475 mca, 90Ah

Battery Cable RecommendationsIMPORTANT: Terminals must be soldered to cable ends to ensure good electricalcontact. Use electrical grade (resin flux) solder only. Do not use acid flux solder, asit may cause corrosion and failure.

Cable Length Cable Gauge

Up to 3-1/2 ft (1.1 m) 4 (25 mm2)

3-1/2 - 6 ft (1.1-1.8 m) 2 (35 mm2)

6 - 7-1/2 ft (1.8-2.3 m) 1 (50 mm2)

7-1/2 - 9-1/2 ft (2.3-2.9 m) 0 (50 mm2)

9-1/2 - 12 ft (2.9-3.7 m) 00 (70 mm2)

12 - 15 ft (3.7-4.6 m) 000 (95 mm2)

15 - 19 ft (4.6-5.8 m) 0000 (120 mm2)

Both positive (+) and negative (–) cables


Page 4A-4 90-861329--1 MARCH 1999

Starting System Components

72929

I

BC A

a

h

b

e

c

d

f

g

a - Ignition Switchb - Neutral Safety Switchc - Starter Slave Solenoidd - Circuit Breaker (not on all models)e - Engine Ground Studf - Starter Solenoidg - Wire Junctionh - 20 Amp Fuse


90-861329--1 MARCH 1999 Page 4A-5


WARNINGElectrical, ignition and fuel system components on your MerCruiser are designedand manufactured to comply with U.S. Coast Guard Rules and Regulations to mini-mize risks of fire and explosion.

Use of replacement electrical, ignition or fuel system components that do not comply withthese rules and regulations could result in a fire or explosion hazard and should be avoided.

Maintenance

WARNINGDo not use jumper cables and a booster battery to start engine. Do not recharge aweak battery in the boat. Remove battery and recharge in a ventilated area awayfrom fuel vapors, sparks or flames.

WARNINGBatteries contain acid which can cause severe burns. Avoid contact with skin, eyesand clothing. Batteries also produce hydrogen and oxygen gases when beingcharged. This explosive gas escapes fill/vent cell caps and may form an explosiveatmosphere around the battery for several hours after it has been charged; sparksor flames can ignite the gas and cause an explosion that may shatter the battery andcould cause blindness or other serious injury.

Safety glasses and rubber gloves are recommended when handling batteries orfilling with electrolyte. Hydrogen gases that escape from the battery duringcharging are explosive. When charging batteries, be sure battery compartment, orarea where battery is located, is well vented. Battery electrolyte is a corrosive acidand should be handled with care. If electrolyte is spilled or splashed on any part ofthe body, immediately flush the exposed area with liberal amounts of water andobtain medical aid as soon as possible.

CAUTIONTo prevent damage to the electrical system be sure to adhere to the following:

• When installing battery, be sure to connect the POSITIVE (+) battery cable toPOSITIVE (+) battery terminal first and then the NEGATIVE (–) battery cable toNEGATIVE (–) battery terminal.

• Never disconnect the battery cables while the engine is running.

• If a charger or booster is to be used, be sure to connect it in parallel with existingbattery (positive to positive and negative to negative).

• When applying a booster charge to battery, disconnect both cables from battery(to prevent damage to voltage regulator).

• Check battery condition periodically.

• Make sure that battery leads are kept clean and tight.


Page 4A-6 90-861329--1 MARCH 1999

1. Ensure that the battery meets the following certain conditions before testing:

CAUTIONTest battery in well ventilated area as gases given off by battery are hazardous.

• Battery must be 60 to 100°F (16 to 38°C).

• Electrolyte level must be correct in all cells.

• Battery must be at least half charged.

• No obvious defects.

2. Place battery under heavy load (as during engine cranking or with a variable resistortester) and test cell voltage while under load:

a. Check voltage per manufacturer’s specifications.

b. If readings are low, recharge and retest.

c. If readings remain low, battery should be replaced.

Storage1. Remove battery and clean exterior.

2. Check fluid level and fill if low.

3. Cover terminals and bolts with light coat of grease.

4. Set battery on wood or in carton; store in cool, dry place.

5. Check every 20 days for fluid level and slow charge.

IMPORTANT: A discharged battery can be damaged by freezing.


90-861329--1 MARCH 1999 Page 4A-7

TestingA strong battery must be maintained. If battery shows less than 9-1/2 volts when under start-ing load, (at 80° F or 27° C) it should be recharged. Check with DC voltmeter.

74307

10

0 5

15

10

5

15

b

a

a - Voltmeterb - Battery

Place battery under heavy load (as during engine cranking or with a variable resistor tester)and test cell voltage while under load.

Certain conditions must be met before testing.

• Battery must be 60 to 100°F (16 to 38°C).

• Electrolyte level must be correct in all cells.

• Battery must be at least half charged.

• No obvious defects.

1. Check voltage per manufacturer’s specifications.

2. If readings are low, recharge and retest.

3. If readings remain low, battery should be replaced.


Page 4A-8 90-861329--1 MARCH 1999

Positive Current Flow

This is a general description of the positive current flow, from the battery and through thesystem until the starter motor cranks.

• Battery to the solenoid switch (on starter) (RED battery cable).

• Solenoid switch to circuit breaker (RED).

• Circuit breaker to wire junction (RED-PUR).

• Wire junction to wiring harness plug (RED-PUR) terminal 6.

• Wiring harness plug to 20 amp fuse (RED-PUR).

• 20 amp fuse to ignition switch terminal I (RED-PUR). At this point ignition switch is turnedto START.

• Ignition switch terminal I to terminal C.

• Ignition switch terminal C to neutral start switch (YEL-RED). NEUTRAL STARTSWITCH MUST BE AT NEUTRAL POSITION.

• Neutral start switch to wiring harness plug terminal 7 (YEL-RED).

• Wiring harness plug to starter solenoid (small terminal) (YEL-RED). Also ensure thatblack (small terminal) wire is grounded.

• Starter solenoid is now “closed,” completing circuit between large terminal (RED-PUR)and other large terminal (YEL-RED), causing starter motor to crank.


90-861329--1 MARCH 1999 Page 4A-9

Charging Guide

12 Volt Battery Recommended Rate* and Time for Fully Discharged Condition

Twenty HourRating

5Amperes

10Amperes

20Amperes

30Amperes

40Amperes

50Amperes

50Ampere-Hours or

less10 Hours 5 Hours 2-1/2

Hours2 Hours

Above 50 to 75Ampere-Hours

15 Hours 7-1/2Hours

3-1/2Hours

2-1/2Hours

2 Hours 1-1/2Hours

Above 75 to 100Ampere-Hours

20 Hours 10 Hours 5 Hours 3 Hours 2-1/2Hours

2 Hours

Above 100 to150

Ampere-Hours30 Hours 15 Hours 7-1/2

Hours5 Hours 3-1/2

Hours3 Hours

Above 150Ampere-Hours

20 Hours 10 Hours 6-1/2Hours

5 Hours 4 Hours

* Initial rate for constant voltage taper rate charger

To avoid damage, charging rate must be reduced or temporarily halted, if:

1. Electrolyte temperature exceeds 125° F (52° C).

2. Violent gassing or spewing of electrolyte occurs.

Battery is fully charged when, over a two hour period at a low charging rate in amperes, allcells are gassing freely and no change in specific gravity occurs. For the most satisfactorycharging, the lower charging rates in amperes are recommended.

Full charge specific gravity is 1.260-1.280, corrected for temperature with electrolyte levelat split ring.

Battery Power as Affected by Temperature

74310

100%

83%

61%

45%

80°F(27°C)

32°F (0°C)

0°F(-18°C)

-20°F(-29°C)

100%

165%

250%

350%

Power (Watts) Available Power (Watts) Required


Page 4A-10 90-861329--1 MARCH 1999

Slave Solenoid IdentificationTypes

There are two types of slave solenoids (“standard” or “switch”) used on MerCruiser engines.These engines use a standard type solenoid; do not substitute a switch type solenoid.The other engines use a slave solenoid to energize the starter motor solenoid. Some modelengines use the small terminal on the “switch type” solenoid for ignition by-pass during thestarting of the engine. Because of this, be sure to use correct type of slave solenoid for re-placement.

Standard Type Slave Solenoid

a b

c d e

a

c

b

74581

Starting Position Off Or Run Positiona - From Key Switch (12 Volts In Start Position)b - To Groundc - 12 Volts From Batteryd - 0 Volts From Startere - 12 Volts To Starter

Switch Type Slave Solenoid

74582

b

a

c d

e

f

g

b

a

c

Starting Position Off Or Run Positiona - From Key Switch (12 Volts in Start Position)b - Mounting Bracket and Groundc - 12 Volts from Batteryd - 0 Volts To Startere - 0 Volts To Ignition Coilf - 12 Volts To Starterg - 12 Volts To Ignition Coil


90-861329--1 MARCH 1999 Page 4A-11

Testing/Replacement1. Using continuity meter, connect test leads as shown and connect 12-volt battery with

jumper leads as shown.

72630

2. If no meter movement is present, replace solenoid.

Solenoid Switch

The solenoid switch, along with plunger, return spring, and shift lever, are completely sealedand permanently mount-ed in the drive housing. If solenoid is defective, entire drive housingmust be replaced.

Periodic Inspection

Cranking motor and solenoid are completely enclosed in the drive housing to prevententrance of moisture and dirt. However, periodic inspection is required as follows:

1. Inspect terminals for corrosion and loose connections.

2. Inspect wiring for frayed and worn insulation.

3. Check starter mounting bolts for tightness.


Page 4A-12 90-861329--1 MARCH 1999

PG260 Starter Motor

PG260 Specifications

Delco I.D. Number MerCruiser Part Number

9000820 50-806963

No Load Test Brush SpringEngineRotation Volts Min.

Amps Max. Amp Min. rpm Max. rpm

Brush SpringTension Oz.

(Grams)

LH 10.6 60 95 2750 3250 83-104 oz. (2352-2948)

Pinion Clearance .101-.160 (.025-4.06mm)

Bearing Depth (Gear) .011-.014 (0.28-.038mm) Maximum

Bearing Depth (Housing) .009-.017 (0.4mm) Maximum

Torque Specification

Fastener Location lb-ft Nm

Starter Mounting Bolts 30 41

Fastener Not Listed Tighten Securely

NOTE: The PG260 starter cannot be rebuilt. The only replacement components availableare the solenoid and drive housing.

DescriptionThe Delco PG260 starter motor features small permanent magnets mounted inside the fieldframe. These magnets take the place of current-carrying field coils mounted on iron polepieces. Internal gear reduction, approximately 4 to 1, through planetary gears results inarmature speeds in the 7000 rpm range. The armature and drive shaft are mounted on rolleror ball bearings in place of bushings. The solenoid switch, plunger, return spring, and shiftlever are permanently mounted in the drive housing.

CAUTIONThe starter motor is designed to operate under great overload and produce a highhorsepower for its size. It can do this only for a short time, since considerable heataccumulates and can cause serious damage. For this reason, the cranking motormust never be used for more than 30 seconds at any one time. Cranking should notbe repeated without a pause of at least 2 minutes to permit the heat to escape.


90-861329--1 MARCH 1999 Page 4A-13

PG260 Exploded View

74270

��

�

�

�

�

�

�

�

��

��

��

��

��

��

��

��

�

�

��

1 - Screw (2)2 - End Cap3 - Brush With Holder4 - Armature5 - Field Frame (With Permanent Magnets)6 - Washer7 - Shield8 - Planetary Gears9 - Shaft

10 - Gear11 - Drive12 - Collar13 - Retaining Ring14 - Trust Collar15 - Drive Housing16 - Nut17 - Solenoid18 - Solenoid Drive Arm19 - Screw (3)20 - Screw (2)21 - Rubber Grommet


Page 4A-14 90-861329--1 MARCH 1999

Starter Motor Repair

Removal

WARNINGDisconnect battery cables at battery before removing starter.

1. Disconnect battery cables from battery.

2. Disconnect wires from solenoid terminals.

IMPORTANT: Some starter motors may use a special mounting shim for gaining fly-wheel clearance. Do not lose this shim; it will be needed when remounting starter onengine block.

3. Remove starter mounting bolts.

4. Pull starter assembly away from flywheel and remove from engine.

74523

a

a - Starter Bracket (If So Equipped)

Disassembly1. Remove brush lead from solenoid and screws from end frame.

74041

a

b

a - Brush Leadb - Screws


90-861329--1 MARCH 1999 Page 4A-15

2. Remove through bolts and separate end frame from field frame and end cap.

74040

a

b

c

a - End Capb - Through Boltc - Drive Housing

3. Remove brush holder from end cap.

74037ab

c

a - Brush Holderb - End Capc - Screws (2)

4. Remove armature and field frame from drive housing.

5. Pull armature out of field frame.

NOTE: Permanent magnets inside field frame will be holding armature in place.

74086b a

a - Armatureb - Field Frame


Page 4A-16 90-861329--1 MARCH 1999

6. Remove shield and washer.

74038

a b

a - Shieldb - Washer

7. Remove the three screws retaining the solenoid. Remove solenoid from drive housing.

74036

b

a

c

a - Drive Housingb - Solenoidc - Screws (3)

8. Remove drive and associated parts from drive housing.

74035

a b

a - Drive Housingb - Drive


90-861329--1 MARCH 1999 Page 4A-17

9. Remove solenoid arm and rubber grommet from the drive housing.

74018

74048

74105a

c

b

a - Rubber Grommetb - Solenoidc - Drive Housing

10. Remove thrust collar, retaining ring and collar from planetary shaft.

74016d

a

b

c

a - Thrust Collarb - Retaining Ringc - Collard - Drive


Page 4A-18 90-861329--1 MARCH 1999

11. Remove drive and gear from planetary shaft.

74087

a

b

c

a - Gearb - Planetary Gear Shaft Assemblyc - Drive

Cleaning and InspectionIMPORTANT: Do not use grease dissolving solvents to clean electrical components,planetary gears, or drive. Solvent will damage insulation and wash the lubricant outof the drive and gears. Use clean rags and compressed air to clean components.

1. Test over-running clutch action of drive. Pinion should turn freely in over-running direc-tion and must not slip in cranking direction. Check pinion teeth. Check spring for tensionand drive collar for wear. Replace if necessary.

2. Check that brush holders are not damaged or bent and hold brushes againstcommutator. Check brushes for wear; refer to “Brushes and Brush Holder.”

3. Inspect armature commutator. If badly grooved or out-of-round, turn down and undercutcommutator.

4. Inspect all roller bearing surfaces for wear. Check that bearings roll freely. If anyroughness is felt, replace bearings.

5. Inspect planetary gear assembly. Gears must mesh easily and roll freely with no binding.


90-861329--1 MARCH 1999 Page 4A-19

Armature Tests

TEST FOR SHORTS

Check armature for shorts by placing on growler and holding hack saw blade over armaturecore while rotating armature. If saw blade vibrates, armature is shorted. After cleaningbetween commutator bars, recheck. If saw blade still vibrates, replace armature.

01440

a

b

c

a - Hacksaw Bladeb - Armature Coverc - Growler

TEST FOR GROUND

1. With continuity meter, place one lead on armature core or shaft and other lead oncommutator.

2. If meter hand moves, armature is grounded and must be replaced.

01441

d

a

b c

a - Commutatorb - Armature Corec - Shaftd - Growler


Page 4A-20 90-861329--1 MARCH 1999

Armature Bearing (Commutator End)

REMOVAL

Use a universal puller plate, as shown, to remove bearing.

72068

a b

a - Universal Puller Plateb - Bearing

INSTALLATION

IMPORTANT: Brush holder must be installed on armature before installing armaturebearing.

Using the correct size driver, press on inner bearing race until it contacts shoulder ofarmature shaft.

Gear Bearing

REMOVAL

Using the correct size driver, press bearing out of gear.

INSTALLATION

1. Using the correct size driver, press bearing into gear, from direction shown, to depthspecified.

72625

a

b

a - Depth - .011-.014 in. (0.28-0.38 mm)b - Installation Direction


90-861329--1 MARCH 1999 Page 4A-21

2. Lubricate bearing and gear teeth with a small amount of Quicksilver 2-4-C MarineLubricant with Teflon.

Shaft Assembly BearingIMPORTANT: Roller bearing is not replaceable. If bearing is defective, replace entireshaft assembly. Apply Quicksilver 2-4-C Marine Lubricant with Teflon to bearingbefore starter reassembly.

72070

a

a - Roller Bearing

Drive End Housing Bearing

REMOVAL

Using the correct size driver, press bearing out of housing.

72626

b

a

a - Drive End Housingb - Bearing


Page 4A-22 90-861329--1 MARCH 1999

INSTALLATION

1. Using the correct size driver, press bearing into housing, from direction shown, to depthspecified.

72626

a

b

a - Depth - .009-.017 in. (0.25-0.45 mm)b - Installation Direction

2. Lubricate bearing with a small amount of Quicksilver 2-4-C Marine Lubricant with Teflon.

Brushes and Brush Holder

INSPECTION

Replace brushes and holder when brush leads are touching guide.

Make sure brushes move freely in guides.

72069

b

a

a - Brush Leadsb - Guide

REMOVAL

1. Remove armature bearing as previously described.

2. Remove brush holder.


90-861329--1 MARCH 1999 Page 4A-23

INSTALLATION

1. Push each brush up into its guide to allow spring to hold it in place, as shown.

72072

b

ac

a - Brushb - Guidec - Brush Spring

2. Place brush holder on armature and push brushes down against commutator, as shown.

72069

ab

c

a - Brush Holderb - Brushc - Commutator

3. Install armature bearing as previously described.


Page 4A-24 90-861329--1 MARCH 1999

Reassembly1. Install end frame on brush holder. Align holes of end frame with holes of brush holder.

Tighten screws securely.

ad

b

c

76250

a - Screw (2)b - End Capc - Brush Holderd - Armature

2. Install gear and drive over planetary shaft.

74087

a

b c

a - Planetary Shaftb - Gearc - Drive


90-861329--1 MARCH 1999 Page 4A-25

3. Assemble drive on shaft assembly as follows:

a. Lubricate drive end of shaft assembly with SAE 10W oil.

b. Place gear over shaft.

c. Slide drive assembly onto shaft with pinion facing outward.

d. Slide retainer onto shaft with cupped surface facing end of shaft (away from pinion).

e. Position snap ring on upper end of shaft and hold in place with block of wood. Strikewood block with hammer, thus forcing snap ring over end of shaft. Slide snap ringdown into groove.

ab

c

72073

a - Snap Ringb - Groovec - Retainer

f. Assemble thrust collar on shaft with shoulder next to snap ring.

g. Position retainer and thrust collar next to snap ring. Then, using two pliers, gripretainer and thrust collar and squeeze until snap ring is forced into retainer.

72074

a

b

c

a - Retainerb - Thrust Collarc - Snap Ring


Page 4A-26 90-861329--1 MARCH 1999

4. Install the planetary gears on planetary shaft.

5. Install solenoid arm and rubber grommet in the drive housing.

74018

74048

74105a

c

b

a - Rubber Grommetb - Solenoidc - Drive Housing

6. Install drive and associated parts in drive housing.

74035

a b

a - Drive Housingb - Drive


90-861329--1 MARCH 1999 Page 4A-27

7. Place solenoid in drive housing and tighten screws.

74036

b

a

c

a - Drive Housingb - Solenoidc - Screw (3)

8. Install shield and washer in drive housing.

74038

a b

a - Shieldb - Washer

9. Install field frame over armature. Align slot in end cap and field frame for proper position-ing of rubber grommet.

76251


Page 4A-28 90-861329--1 MARCH 1999

10. Install field frame and end cap in drive housing align slots in field frame with recess indrive housing.

ab 76252

a - Drive Housingb - End Cap and Field Frame

11. Install through bolts and brush lead. Tighten fasteners securely.

Starter Solenoid

Testing/Replacement1. Using continuity meter, connect test leads as shown, and connect 12 volt battery with

jumper leads as shown.

72630

a - Brush Lead

2. If no meter movement is present, replace solenoid.

3. Install through bolts and brush lead. Tighten fasteners securely.

4. Connect 12 volt battery positive (+) lead to solenoid switch terminal and negative (–)lead to solenoid frame.


90-861329--1 MARCH 1999 Page 4A-29

5. Momentarily touch a jumper lead from solenoid motor to starter motor frame. This shiftspinion into cranking position where it will remain until battery is disconnected.

72629

6. Push pinion back toward commutator end to eliminate slack.

7. Measure distance between pinion and pinion retainer.

8. If clearance is not within limits of .010-.160 in. (0.25-4.00 mm), it may indicate excessivewear of solenoid linkage, shift lever yoke, or improper assembly of shift levermechanism. Replace worn or defective parts, since no provision is made for adjustingpinion clearance.

72077

ab

c

a - Pinionb - Retainerc - Feeler Gauge


Page 4A-30 90-861329--1 MARCH 1999

InstallationIMPORTANT: Install special mounting shim (if equipped) between starter motor andengine block.

1. Place starter motor in position and install mounting bolts. Torque bolts to 30 lb-ft (41 Nm).

2. Connect YELLOW/RED wire to terminal S of solenoid. Connect ORANGE wire, REDwire, and battery cable to large terminal of solenoid. Tighten fasteners securely. Coatterminals with Quicksilver Liquid Neoprene. Install battery cable boot, if so equipped.

3. Connect battery cables to battery in the following order. Connect positive (+) cable topositive (+) battery terminal and tighten cable clamp. Then connect negative (–) cableto negative (–) terminal and tighten clamp.


90-861329--1 MARCH 1999 Page 4A-31

PG260F1 Starter Motor

PG260F1 Specifications

Delco I.D. Number MerCruiser Part Number

9000839 - 9000840 50-807904

No Load Test Brush SpringEngineRotation Volts Min.

Amps Max. Amp Min. rpm Max. rpm

Brush SpringTension Oz.

(Grams)

LH 11.5 40 90 3200 4800

Brush Spring LengthLength New - 0.36 - 0.42 in. (9.2 - 10.7 mm)

Length Used - 0.18 - 0.23 in. (4.62 - 5.98 mm)

Pinion Clearance 0.009 - 0.160 in. (0.23-4.06 mm)

Bearing Depth (Gear) Flush - Inside

Bearing Depth (Housing) .009-.017 (0.4mm) Maximum



Starter Mounting Bolts 30 41

All Other Fasteners Tighten Securely

Lubricants/Sealants



Quicksilver 2-4-C Marine Lubricant With Teflon 92-825407A3

DescriptionThe Permanent Magnet Gear Reduction (PG200 and PG250) starter motors feature smallpermanent magnets mounted inside the field frame (NOTE: The actual configuration ofthese magnets differs between the PG200, PG250 and PG260; the field frames withpermanent magnets are not interchangeable. Otherwise, the units are similar.) Thesemagnets take the place of current-carrying field coils mounted on iron pole pieces. Internalgear reduction, approximately 4 to 1, through planetary gears results in armature speedsin the 7000 rpm range. The armature and drive shaft are mounted on roller or ball bearingsin place of bushings. The solenoid switch, plunger, return spring, and shift lever arepermanently mounted in the drive housing.

CAUTIONThe starter motor is designed to operate under great overload and produce a highhorsepower for its size. It can do this only for a short time, since considerable heataccumulates and can cause serious damage. For this reason, the cranking motormust never be used for more than 30 seconds at any one time. Cranking should notbe repeated without a pause of at least 2 minutes to permit the heat to escape.


Page 4A-32 90-861329--1 MARCH 1999

Exploded View

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�

�

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90-861329--1 MARCH 1999 Page 4A-33

1 - Screw (2)2 - End Frame and Bearing3 - Brush With Holder4 - Armature5 - Field Frame (With Permanent Magnets)6 - Washer7 - Shield8 - Planetary Gears9 - Shaft

10 - Gear11 - Drive12 - Collar13 - Retaining Ring14 - Trust Collar15 - Drive Housing16 - Nut17 - Solenoid18 - Solenoid Drive Arm19 - Screw (3)20 - Long Screw (2)21 - Rubber Grommet22 - Metal Disc

Starter Motor Repair

Removal

WARNINGDisconnect battery cables at battery before removing starter.


2. Disconnect wires from solenoid terminals.

IMPORTANT: Some starter motors may use a special mounting shim for gaining fly-wheel clearance. Do not lose this shim; it will be needed when remounting starter onengine block.

3. Remove starter mounting bolts.

4. Pull starter assembly away from flywheel and remove from engine.

Disassembly1. Remove brush lead from solenoid and long screws from end frame.

75820

a

b

a- Brush Leadb- Screws


Page 4A-34 90-861329--1 MARCH 1999

2. Separate end frame from field frame.

3. Remove brush holder from end frame.

4. Remove armature and field frame from drive housing.

5. Pull armature out of field frame.

NOTE: Permanent magnets inside field frame will be holding armature in place.

��

b

a

c

d

e

a- End Frame and Bearingb- Screws (2)c- Brush Holderd- Armaturee- Field Frame

6. Remove shield and washer from drive housing.

74038

c

b

aa- Shieldb- Washerc- Drive Housing


90-861329--1 MARCH 1999 Page 4A-35

7. Remove the three screws retaining the solenoid. Remove solenoid from drive housing.

74036

c

b

aa- Drive Housingb- Solenoidc- Screws (3)

8. Remove drive and associated parts from drive housing.

74035 75821ab

a- Drive Housingb- Drive

9. Remove solenoid arm, metal disc and rubber grommet from the drive housing.

75821

a

bc

d

a- Rubber Grommetb- Metal Discc- Solenoid Armd- Drive Housing


Page 4A-36 90-861329--1 MARCH 1999

10. Remove thrust collar, retaining ring and collar from planetary shaft with drive.

75821

b

ac

d

a- Thrust Collarb- Retaining Ring (Inside Collar)c- Collard- Planetary Shaft and Drive

11. Remove drive and gear from planetary shaft.

74087

a

b

c

Typicala - Gearb- Planetary Gear Shaft Assemblyc- Drive


90-861329--1 MARCH 1999 Page 4A-37

Cleaning and InspectionIMPORTANT: Do not use grease dissolving solvents to clean electrical components,planetary gears, or drive. Solvent will damage insulation and wash the lubricant outof the drive and gears. Use clean rags and compressed air to clean components.

1. Test over-running clutch action of drive. Pinion should turn freely in over-running direc-tion and must not slip in cranking direction. Check pinion teeth. Check spring for tensionand drive collar for wear. Replace if necessary.

2. Check that brush holders are not damaged or bent and hold brushes against commuta-tor. Check brushes for wear.

3. Inspect armature commutator. If badly grooved or out-of-round, turn down and undercutcommutator.

4. Inspect all roller bearing surfaces for wear. Check that bearings roll freely. If any rough-ness is felt, replace bearing.

5. Inspect planetary gear assembly. Gears must mesh easily and roll freely with no binding.

Armature Tests

TEST FOR SHORTS

Check armature for shorts by placing on growler and holding hack saw blade over armaturecore while rotating armature. If saw blade vibrates, armature is shorted. After cleaningbetween commutator bars, recheck. If saw blade still vibrates, replace armature.

01440

a

b

c

a- Hacksaw Bladeb- Armature Corec- Growler


Page 4A-38 90-861329--1 MARCH 1999

TEST FOR GROUND

1. With continuity meter, place one lead on armature core or shaft and other lead on com-mutator.

2. If meter hand moves, armature is grounded and must be replaced.

01441

d

a

b c

a- Commutatorb- Armature Corec- Shaftd- Growler

Reassembly1. Install brush holder and bearing on armature.

2. Align brush lead grommet with field frame cut-out. Align holes of end frame with holesof brush holder and drive housing. Install end frame on brush holder. Tighten screwssecurely.

75821

d

c

b

a

a- Screw (2)b- End Framec- Brush Holderd- Armature


90-861329--1 MARCH 1999 Page 4A-39

3. Install gear and drive over planetary shaft.

74087

a

b

c

Typicala - Planetary Gear Shaft Assemblyb- Gearc- Drive

4. Assemble drive on shaft assembly as follows:

a. Lubricate drive end of shaft assembly with SAE 10W oil.

b. Place gear over shaft.

c. Slide drive assembly onto shaft with pinion facing outward.

d. Slide retainer onto shaft with cupped surface facing end of shaft (away from pinion).

e. Position snap ring on upper end of shaft and hold in place with block of wood. Strikewood block with hammer, thus forcing snap ring over end of shaft. Slide snap ringdown into groove.

72073

cb

a

a- Snap Ringb- Groovec- Retainer


Page 4A-40 90-861329--1 MARCH 1999

f. Assemble thrust collar on shaft with shoulder next to snap ring.

g. Position retainer and thrust collar next to snap ring. Then, using two pliers, gripretainer and thrust collar and squeeze until snap ring is forced into retainer.

72074

b

a c

a- Retainerb- Thrust Collarc- Snap Ring

5. Install the planetary gears on planetary shaft.

6. Install solenoid arm, metal disc and rubber grommet in the drive housing.

NOTE: Solenoid arm is designed to fit only one way. Do not use force.

75821

a

bc

d

a- Rubber Grommetb- Metal Discc- Solenoid Armd- Drive Housing


90-861329--1 MARCH 1999 Page 4A-41

7. Install drive and associated parts in drive housing.

7403575821a

b

a- Drive Housingb- Drive

8. Attach solenoid arm to solenoid. Place solenoid in drive housing and tighten screws.

74036

ba

c

a- Drive Housingb- Solenoidc- Screw (3)

9. Install washer and shield in drive housing.

74038

75821a

c

b

a- Washerb- Shieldc- Drive Housing


Page 4A-42 90-861329--1 MARCH 1999

10. Install field frame over armature. Align slot in field frame with rubber grommet.

75821

b c

a

a- Armatureb- Field Frame Slotc- Rubber Grommet

11. Install field frame and end frame in drive housing.

12. Install long screws and brush lead. Tighten fasteners securely.

75821

e

a

c

bd

a- End Frameb- Field Framec- Drive Housingd- Long Screwse- Brush Lead

Starter Solenoid

TESTING / REPLACEMENT

Pinion clearance must be checked after reassembly of starter motor.

1. Disconnect brush lead from solenoid motor and insulate it carefully.

74041

a

a- Brush Lead

2. Connect 12 volt battery positive (+) lead to battery terminal and negative (–) lead toframe.


90-861329--1 MARCH 1999 Page 4A-43

3. Momentarily touch a jumper lead from battery terminal to switch terminal. This shifts pin-ion into cranking position where it will remain until battery is disconnected.

72629

4. Push pinion back toward commutator end to eliminate slack.

5. Measure distance between pinion and pinion retainer.

6. If clearance is not within limits of .010-.160 in. (0.25-4.00 mm), it may indicate excessivewear of solenoid linkage, shift lever yoke, or improper assembly of shift lever mecha-nism. Replace worn or defective parts, since no provision is made for adjusting pinionclearance.

72077

a

b

c

a- Pinionb- Retainerc- Feeler Gauge


Page 4A-44 90-861329--1 MARCH 1999

InstallationIMPORTANT: Install special mounting shim (if equipped) between starter motor andengine block.

1. Place starter motor in position and install mounting bolts. Torque bolts to 30 lb-ft (41 Nm).

2. Connect YELLOW/RED wire to terminal S of solenoid. Connect ORANGE wire, REDwire, and battery cable to large terminal of solenoid. Tighten fasteners securely. Coatterminals with Quicksilver Liquid Neoprene. Install battery cable boot, if so equipped.

3. Connect battery cables to battery in the following order. Connect positive (+) cable topositive (+) battery terminal and tighten cable clamp. Then connect negative (–) cableto negative (–) terminal and tighten clamp.

4B

IGNITION SYSTEMSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 4B-1

ELECTRICAL SYSTEMSection 4B - Ignition System

Table of Contents

Identification 4B-2. . . . . . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 4B-2. . . . . . . . . . . . Torque Specifications 4B-2. . . . . . . . . . . . . . . . . . Tools 4B-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Special Tools 4B-3. . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 4B-3. . . . . . . . . . Specifications 4B-4. . . . . . . . . . . . . . . . . . . . . . . . .

Timing 4B-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . Spark Plugs 4B-4. . . . . . . . . . . . . . . . . . . . . . . . GM 4-Cylinder In-line Firing 4B-4. . . . . . . . . .

Description 4B-5. . . . . . . . . . . . . . . . . . . . . . . . . . . Precautions 4B-6. . . . . . . . . . . . . . . . . . . . . . . . . .

Cleaning And Inspection 4B-7. . . . . . . . . . . . . . . Spark Plugs 4B-7. . . . . . . . . . . . . . . . . . . . . . . . Spark Plug Wires 4B-7. . . . . . . . . . . . . . . . . . . Distributor Cap and Rotor 4B-8. . . . . . . . . . . .

Distributor Installation 4B-8. . . . . . . . . . . . . . . . . . Engine Not Disturbed 4B-8. . . . . . . . . . . . . . . Engine Disturbed 4B-9. . . . . . . . . . . . . . . . . . .

Ignition Timing 4B-9. . . . . . . . . . . . . . . . . . . . . . . . Component Tests 4B-12. . . . . . . . . . . . . . . . . . . .

Testing Ignition Module 4B-12. . . . . . . . . . . . . Testing Ignition Coil 4B-13. . . . . . . . . . . . . . . . Testing Pickup Coil 4B-13. . . . . . . . . . . . . . . .

Advance Curve 4B-15. . . . . . . . . . . . . . . . . . . . . .

IGNITION SYSTEM SERVICE MANUAL NUMBER 26

Page 4B-2 90-861329--1 MARCH 1999

Identification

70103

DELCO EST (Electric Spark Timing)



Use of replacement electrical, ignition or fuel system components, which do notcomply with these rules and regulations, could result in a fire or explosion hazardand should be avoided.



Distributor Clamp 3/8-16 20 27

Spark Plugs (14 mm) 22 30


90-861329--1 MARCH 1999 Page 4B-3

Tools


Dwell Meter 91-59339

Magneto Analyzer 91-76032

Remote Starter Switch 91-52024A1

Timing Light 91-99379

Volt / Ohm Meter 91-99750A1

Timing Jumper 91-818812A1

Point Spring Tension Gauge Obtain Locally

Special Tools

Kent-Moore Special Tools

Kent-Moore Special Tools29784 Little Mack


Module Tester J24642



Distributor Cam Lubricant Obtain Locally

Liquid Neoprene 92-25711--3

Silicone Dielectric Compound 92-802882A1

Heat Transfer Compound 92-805701, 92-805701--1


Page 4B-4 90-861329--1 MARCH 1999

Specifications

Timing

Timing (At Idle rpm)1 1° BTDC2 / 1° ATDC3 / 2° ATDC4

1Timing must be set using a special procedure as outlined in this section. Timing cannot be properly set usingthe conventional method.2Serial number break: 0L096999 and below3Serial number break: 0L097000 - 0L03409994Serial number break: 0L341000 and above.

Spark Plugs

Spark Plug Gap .035 In. (0.9 mm)

3.0LAC-MR43LTS

NGK-BPR6EFSChampion RS12YC

GM 4-Cylinder In-line Firing

50683



90-861329--1 MARCH 1999 Page 4B-5

Description

EST or Electronic Spark Timing is a High Energy Ignition System (HEI). The distributor itselfhas no centrifugal advance mechanism or devices.

The spark plug wires are a carbon-impregnated cord conductor with a silicone rubber jacket.It is important they be handled with care, and routed so as not to cross each other or to bein contact with other parts of the engine to prevent rubbing.

The EST System uses a square coil with epoxy covered windings to protect against mois-ture and arc-over.

The timing cannot be set the same way that other ignition systems were.

70106

b c

e

d

f

a

a - Distributor with Spark Plug Wiresb - Wires (WHITE) Used in Timing Procedurec - Wire from Shift Interrupt Switchd - Distributor Harnesse - Engine Harness Wire (PURPLE AND GRAY)f - Coil

EST uses a magnetic pulse generator and an electronic module to primary circuit current.Internally the Pulse Generator, or magnetic pick-up assembly, takes the place of conven-tional points. A timer core on the main shaft of the distributor has external teeth which alignwith an equal number of pole piece teeth (four for a four cylinder engine). The electronicmodule is small enough to allow it to be mounted inside the distributor, and contains the cir-cuits necessary for dwell control and advance of the timing.


Page 4B-6 90-861329--1 MARCH 1999

Molded into the module is a two-prong connector for the coil terminals and four prong con-nector. Only three of the four terminals of the second connector are used by MerCruiser (onefor the shift interrupt and two white leads are used to “freeze” advance for properly settinginitial timing). Inside the distributor, the pick-up coil attaches to the module at a molded prongconnector.

70107

a

bc

d

e

f

g

h

a - Magnetic Pulse Generatorb - Electronic Modulec - Two Prong Connectord - Four Prong Connectore - Pick-up Coil Connectorf - Timer Coreg - Pole Piece Teethh - External Teeth

Precautions

WARNINGWhen performing the following procedure, be sure to observe the following:

• Be sure that engine compartment is well ventilated and that no gasoline vaporsare present, to avoid the possibility of fire.

• Be sure to keep hands, feet and clothing clear of moving parts.

• Do not touch or disconnect any ignition system parts while engine is running.

• Do not reverse battery cable connections. System is negative (–) ground.

• Do not disconnect battery cables while engine is running.


90-861329--1 MARCH 1999 Page 4B-7

Cleaning And InspectionSpark Plugs

1. Inspect each plug individually for badly worn electrodes, glazed, broken or blisteredporcelain and replace plug where necessary.

2. Inspect each spark plug for manufacturer and heat range. All plugs must be the samemanufacturer and number or heat range. Refer to “Specifications” for spark plug num-bers.

3. Check spark plug gaps with a round feeler gauge. Adjust if necessary.

50674

a e

bc

d

f

Spark Plug Detaila - Porcelain Insulatorb - Check For Cracks In This Area of Porcelainc - Shelld - Proper Gape - Side Electrode (Gap Adjustment)f - Center Electrode (File Flat When Adjusting Gap)

IMPORTANT: Tapered seat spark plugs are not interchangeable with non-tapered(with gasket) spark plugs.

4. Clean spark plug seating area. DO NOT use gaskets on taper seat plugs. Install sparkplugs and torque to 22 lb-ft (30 Nm). Heat transfer and a gas-tight seal must be achieved.

Spark Plug Wires1. Inspect spark plug wires for damage.

2. Check spark plug wires for continuity.

3. Replace any wires that are cracked, cut or have damaged spark plug boots.

4. Replace any wires that do not show continuity from end to end.

5. Reinstall spark plug wires in proper order.

IMPORTANT: Proper positioning in spark plug wires is important to prevent crossfiring.


Page 4B-8 90-861329--1 MARCH 1999

Distributor Cap and Rotor1. Loosen distributor cap retaining screws.

2. Remove distributor cap.

3. Clean cap with warm soap and water and blow off with compressed air.

4. Check cap contact for excessive burning or corrosion. Check center contact fordeterioration.

IMPORTANT: Distributor caps (for marine use) should have brass contacts, alumi-num contacts should not be used.

5. Check cap for cracks or carbon tracks using magneto analyzer.

6. Remove rotor.

7. Check for burned or corroded center contact.

8. Check rotor for cracks and carbon tracks using magneto analyzer.

9. Install rotor on shaft. Be sure rotor is completely seated on shaft.

10. Place cap on distributor.

11. Tighten retaining screws securely.

Distributor Installation

Engine Not Disturbed1. Install new gasket on distributor housing.

2. Turn rotor approximately 1/8 turn in a counter-clockwise direction past mark previouslyscratched on distributor housing.

3. Work distributor down into position in engine block with distributor positioned as notedduring removal.

IMPORTANT: It may be necessary to move rotor slightly to start gear into meshcamshaft gear, but rotor should line up with mark when distributor is down in place.Distributor shaft must enter oil pump shaft for complete installation.

4. Replace and tighten distributor hold-down bolt and clamp. Connect primary lead to coil.Also install spark plug and coil secondary wires, if removed.

IMPORTANT: Wires must be installed in supports, to prevent cross-firing. Firingorder is 1-3-4-2.

5. Install rotor.

6. Time ignition as outlined under “Ignition Timing,” in this section.

7. Replace distributor cap.


90-861329--1 MARCH 1999 Page 4B-9

Engine Disturbed1. Locate No. 1 piston in firing position by either of two methods described below.

a. Remove No. 1 spark plug and, with finger on plug hole, crank engine until compres-sion is felt in No. 1 cylinder. Continue cranking until pointer lines up with timing markon crankshaft pulley, or

b. Remove rocker cover and crank engine until No. 1 intake valve closes, continuingto crank slowly until pointer lines up with timing mark on crankshaft pulley.

2. Position distributor to opening in block in normal installed attitude.

3. Position rotor to point toward front of engine (with distributor housing held in installedattitude), then turn rotor counterclockwise approximately 1/8-turn more to the left andpush distributor down to engage camshaft. It may be necessary to rotate rotor slightlyuntil camshaft engagement is felt.

4. While pressing down firmly on distributor housing, engage starter a few times to makesure oil pump shaft is engaged. Install hold-down clamp and bolt and snug up bolt.

5. Turn distributor body slightly until points just open and tighten distributor clamp bolt.

6. Place distributor cap in position and check that rotor lines up with terminal for No. 1 sparkplug. Install cap.

7. Install cap, distributor primary lead to coil. Check and connect spark plug wires, if theyhave been removed. Wires must be installed in their proper location in supports toprevent cross-firing. Firing order is 1-3-4-2.

8. Install rotor.

9. Replace distributor cap.

10. Time ignition as outlined under “Ignition Timing,” in this section.

Ignition Timing

IMPORTANT: Failure to follow the timing procedure instructions will result inimproper timing causing performance problems and possible severe enginedamage.

1. Connect timing light (91-99379 or similar) to No. 1 spark plug wire. Connect power sup-ply leads on light to 12 volt battery. Refer to Specifications - “Engine Rotation and FiringOrder,” for cylinder numbering and location.

2. Connect a shop tachometer to engine.

NOTE: Before starting engine make sure the timing tab and mark on damper are clean.Chalk or white paint on timing mark on damper may help visibility.


Page 4B-10 90-861329--1 MARCH 1999

3. Start engine and run at idle speed until it reaches normal operating temperature.

70103b

a

a

a - WHITE Leadsb - Jumper Lead

4. Install a jumper wire between the two WHITE leads on the distributor. Use Quicksilver91-818812A1, or fabricate a jumper wire using a 6 in. (150 mm) section of 16 gauge wirewith two male bullet terminal ends connected.

5. Bypass the shift interrupt switch, as follows:

a. Disconnect wires at shift interrupt switch.

b. Temporarily join the engine harness wires together.

75499

75552

IMPORTANT: Do not fail to reconnect these two wires to the shift interrupt switchwhen timing procedures are complete.


90-861329--1 MARCH 1999 Page 4B-11

6. Aim timing light at timing tab, located on the timing gear cover and crankshaft torsionaldamper. Check the timing. Refer to “Specifications.”

72328

73664

Typical

7. Adjust timing by loosening distributor clamp and rotating distributor body as requireduntil timing mark on damper or pulley lines up with the mark on tab specified in“Specifications.” Tighten clamp and recheck location of timing mark.

8. Aim timing light at timing tab and recheck location of timing mark. Repeat Step 7 untiltiming is correct.

9. Stop the engine. Torque distributor hold down bolt to 20 lb-ft (27 Nm).

10. Reconnect the two wires to the shift interrupt switch.

75499

75552

75553


Page 4B-12 90-861329--1 MARCH 1999

IMPORTANT: Be sure to remove jumper wire before returning engine to service,otherwise timing will not advance.

11. Remove jumper wire at distributor white leads.

70103b

a

a

a - WHITE Leadsb - Jumper Lead

12. With timing light still connected, start the engine and run at IDLE. Verify that timing didadvance to :

• If initial timing is 1° BTDC: 12° BTDC, plus or minus 2°. At 2400-2800 rpm maximum(total) advance is obtained and should be 23° BTDC (plus or minus 2°).

• If initial timing is 1° ATDC: 14° BTDC, plus or minus 2°. At 2400-2800 rpm maximum(total) advance is obtained and should be 25° BTDC (plus or minus 2°).

• If initial timing is 2° ATDC: 15° BTDC, plus or minus 2°. At 2400-2800 rpm maximum(total) advance is obtained and should be 26° BTDC (plus or minus 2°).

13. Stop the engine and remove the timing light.

Component Tests

The following tests can be made with the distributor and coil mounted on or off the engine.The test procedures will check each component of the distributor and ignition coil. Distribu-tor cap and rotor should be checked for corrosion, cracks, carbon tracks or wear. Replaceif needed.

Testing Ignition ModuleIn order to test the module, an approved module tester, such as Kent-Moore Tester (J24642or equivalent), must be used. Be certain to follow the manufacturer’s directions preciselyfor proper results. However, do not overlook that corrosion on the terminals of the modulecould cause improper ignition action and should therefor be inspected and cleaned ifneeded.


90-861329--1 MARCH 1999 Page 4B-13

Testing Ignition Coil1. If not already done, disconnect wiring from ignition coil. Connectors are molded and

keyed to assure proper positioning. The terminal (e) feeds 12 volts to the distributor.

NOTE: Upon reinstallation, first install black connector (distributor harness) to coil. Theninstall gray connector (engine harness).

2. Set ohmmeter to “Rx100” scale and connect one lead to 12 volt terminal (b) of coil andthe other lead to “ground” (d), any clean metal on the coil frame. Reading should be infi-nite. If not, replace coil.

3. Set ohmmeter to “Rx100” scale and connect to 12 volt terminal (b) and terminal (c).Reading should be approximately .4 ohms. If not, replace coil.

4. Set ohmmeter to “Rx1” scale and connect to 12 volt terminal (b) and tachometer terminal(f). Reading should be approximately .4 ohms. If not, replace coil.

5. Set ohmmeter to “Rx100” high scale. Connect ohmmeter to 12 volt terminal (b) and tocoil high tension post (a). Reading should be between 7800 and 8800 ohms. If it readsoutside of this range, replace coil.

Testing Pickup Coil

70105

b

c

d

a

a - Connectorb - GREEN Leadc - WHITE Leadd - Distributor Housing

1. Remove distributor cap.

2. Identify the two pickup coil leads. On almost all applications these two leads are oneWHITE and one GREEN. Remove the connector that houses these two leads from themodule.

3. Set ohmmeter to “Rx1” scale. Connect one lead of ohmmeter to WHITE lead and theother to distributor housing. Reading should be infinite. If not, replace pickup coil.


Page 4B-14 90-861329--1 MARCH 1999

4. Repeat Step 3 with ohmmeter connected to GREEN lead. Reading should be infinite.If not, replace pickup coil.

5. Set ohmmeter to “Rx100” scale. Connect ohmmeter to GREEN and WHITE pickup coilleads. Reading should be constant, unchanging value in the range of 500-1500 ohms.If not, replace pickup coil. Be certain to flex leads by hand during this test to locate pos-sible intermittent “open” circuits (loss of continuity). If any exist, replace pickup coil.


90-861329--1 MARCH 1999 Page 4B-15

Advance Curve

Module Part Number: 811637

Module Advance: See Notice

Initial Timing: 1° BTDC1 / 1° ATDC2 / 2° ATDC3

Total Advance: 23°1Serial number break: 0L340999 and below unless specified differently below2Serial number break: 0K001529 - 0L097000 Timing changes to 1° ATDC only if engine experiences a cylinderhead gasket failure that has blown out toward the intake exhaust manifold on the port side of the engine.3Serial number break: 0L341000 and above.

NOTICE

Advance curve includes initial timing. DO NOT add initial timing degrees to totaladvance degrees.

500 1000 1500 2000 2500 3000 3500 4000 4500 5000

5°

10°

15°

20°

25°

30°

35°

ENGINE R.P.M.

TOTA

L S

PAR

K A

DV

AN

CE

70808-15

MAX.

MIN.

Initial Timing 1° BTDC


Page 4B-16 90-861329--1 MARCH 1999

500 1000 1500 2000 2500 3000 3500 4000 4500 5000

5°

10°

15°

20°

25°

30°

35°

ENGINE R.P.M.

TOTA

L S

PAR

K A

DV

AN

CE

70808-15

MAX.

MIN.

Initial Timing 1° ATDC


90-861329--1 MARCH 1999 Page 4B-17

500 1000 1500 2000 2500 3000 3500 4000 4500 5000

5°

10°

15°

20°

25°

30°

35°

ENGINE R.P.M.

TOTA

L S

PAR

K A

DV

AN

CE

70808-15

MAX.

MIN.

Initial Timing 2° ATDC


Page 4B-18 90-861329--1 MARCH 1999


4C

CHARGING SYSTEMSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 4C-1

ELECTRICAL SYSTEMSection 4C - Charging System

Table of Contents

Identification 4C-2. . . . . . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 4C-3. . . . . . . . . . . . Description 4C-3. . . . . . . . . . . . . . . . . . . . . . . . . . . Precautions 4C-4. . . . . . . . . . . . . . . . . . . . . . . . . . System Components 4C-5. . . . . . . . . . . . . . . . . . Periodic Maintenance 4C-6. . . . . . . . . . . . . . . . . . Drive Belt Tension Adjustment 4C-7. . . . . . . . . .

Alternator 4C-7. . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting Tests (Alternator on Engine) 4C-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Circuitry Test 4C-8. . . . . . . . . . . . . . . . . . . . . . . Current Output Test 4C-10. . . . . . . . . . . . . . . . Voltage Output Test 4C-11. . . . . . . . . . . . . . . .

Alternator Repair 4C-12. . . . . . . . . . . . . . . . . . . . . Removal 4C-12. . . . . . . . . . . . . . . . . . . . . . . . . Exploded View 4C-13. . . . . . . . . . . . . . . . . . . . Disassembly 4C-14. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 4C-18. . . . . . . . . . . . Component Testing 4C-19. . . . . . . . . . . . . . . . Reassembly 4C-23. . . . . . . . . . . . . . . . . . . . . .

Installation 4C-28. . . . . . . . . . . . . . . . . . . . . . . . . .

Batteries 4C-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . Battery Cables 4C-29. . . . . . . . . . . . . . . . . . . .

Mando 55 Amp Alternator 4C-30. . . . . . . . . . . . . Identification 4C-30. . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 4C-30. . . . . . . . Specifications 4C-30. . . . . . . . . . . . . . . . . . . . . Tools 4C-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 4C-31. . . . . . Torque Specifications 4C-31. . . . . . . . . . . . . . Battery Isolator Diagram 4C-32. . . . . . . . . . . .

Mando 65 Amp Alternator 4C-33. . . . . . . . . . . . . Identification 4C-33. . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 4C-33. . . . . . . . Specifications 4C-33. . . . . . . . . . . . . . . . . . . . . Tools 4C-34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 4C-34. . . . . . Torque Specifications 4C-34. . . . . . . . . . . . . .

Exploded View 4C-35. . . . . . . . . . . . . . . . . . . . . . .

CHARGING SYSTEM SERVICE MANUAL NUMBER 26

Page 4C-2 90-861329--1 MARCH 1999

Identification

72078

a

b

c

Mando 55 Amp Alternatora - Excitation Wire - PURPLEb - Sensing Wire - RED/PURPLEc - Mando Part Number (Hidden In This View)

76093

Mando 65 Amp Alternator


90-861329--1 MARCH 1999 Page 4C-3




Description

The alternator has a rotor, which is supported in two end frames by ball bearings, and isdriven by a pulley at approximately twice engine speed. The rotor contains a field windingthat is enclosed between two multiple-finger pole pieces. The ends of the field winding areconnected to two brushes (mounted in the rear end frame) which make continuous sliding(or slipping) contact with the slip rings. The current (flowing through the field winding)creates a magnetic field that causes the adjacent fingers of the pole pieces to becomealternate north and south magnetic poles.

A 3-phase stator is mounted directly over the rotor pole pieces and between two end frames.It consists of three windings wound 120 degrees electrically out-of-phase on the inside ofa laminated core. The windings are all connected together on one end, while the other endsare connected to a full-wave rectifier bridge.

The rectifier bridge contains six diodes which are arranged so that current flows fromground, through the stator and to the output terminal, but not in the opposite direction.

When current is supplied to the rotor field winding, and the rotor is turned, the movementof the magnetic fields created induces an alternating current into the stator windings. Therectifier bridge then changes this alternating current to direct current which appears at theoutput terminal. A diode trio also is connected to the stator windings to supply current to theregulator and the rotor field during operation.

Voltage output of the alternator is controlled by regulating the current supplied to the rotorfield. This is accomplished by a transistorized voltage regulator that senses the voltage atthe battery and regulates the field current to maintain alternator voltage within prescribedlimits for properly charging the battery. Current output of the alternator does not require reg-ulation, as maximum current output is self-limited by the design of the alternator. As longas the voltage is regulated within the prescribed limits, the alternator cannot produce exces-sive current. A cut-out relay in the voltage regulator also is not required, as the rectifierdiodes (which allow current to flow in one direction only) prevent the battery from discharg-ing back through the stator.

Due to the lack of residual magnetism in the rotor pole pieces, a small amount of currentmust be supplied to the rotor field to initially start the alternator charging. This is accom-plished by means of an excitation circuit in the regulator which is connected to the ignitionswitch. Once the alternator begins to produce output, field current is supplied solely by thediode trio, as explained, preceding.

The alternator also is equipped with a fan (mounted on the rotor shaft) which induces air flowthrough the alternator to remove the heat created by the rectifiers and stator. A capacitorprotects the rectifier system from high voltages and suppresses radio noise.


Page 4C-4 90-861329--1 MARCH 1999

Precautions

CAUTIONThe following precautions MUST BE observed when working on the alternator system.Failure to observe these precautions may result in serious damage to the alternator oralternator system.

• DO NOT attempt to polarize the alternator.

• DO NOT short across or ground any of the terminals on the alternator, except as spe-cifically instructed in the “Troubleshooting Tests.”

• NEVER disconnect the alternator output lead or battery cables when the alternator isbeing driven by the engine.

• NEVER disconnect regulator lead from alternator regulator terminal when the alterna-tor is being driven by the engine.

• ALWAYS remove negative (–) battery cable from battery before working on alternatorsystem.

• When installing battery, BE SURE to connect the positive (+) battery cable to the posi-tive (+) battery terminal and the negative (–) (grounded) battery cable to negative (–)battery terminal.

• If a charger or booster battery is to be used, BE SURE to connect it in parallel with exist-ing battery (positive to positive; negative to negative).


90-861329--1 MARCH 1999 Page 4C-5

System Components

The alternator system consists of the alternator, battery, the ignition switch and the wiringwhich connects these components.

72933a

b

c

d

e

f

g

h

a - Batteryb - Ground Studc - Starter Motord - Circuit Breaker (not on all models)e - Alternatorf - Harness Plugg - Battery Meterh - Ignition Switch


Page 4C-6 90-861329--1 MARCH 1999

Periodic Maintenance

The following maintenance check should be performed every 50 hours or 60 days(whichever comes first) in fresh water areas or every 25 hours or 30 days in salt water areas.

CAUTIONRemove all battery cables from battery (before conducting the following check) toprevent accidentally shorting out electrical system.

1. Inspect entire alternator system for corroded or loose connectors.

2. Check wiring for frayed or worn insulation.

3. Check alternator drive belt for excessive wear, cracks, fraying and glazed surfaces.Also, check drive belt tension and adjust, if necessary, as explained under “Drive BeltTension Adjustment.”

4. Check alternator mounting bolts for adequate tightness.

5. Inspect slip ring end frame flame arrestor screen for debris and clean, if necessary, usingcompressed air or a cloth. Screen MUST BE clean, or alternator may overheat.

72078a

a - Inspect This Area


90-861329--1 MARCH 1999 Page 4C-7

Drive Belt Tension Adjustment

Alternator1. Install drive belt on pulleys and adjust tension as follows:

a. Pivot alternator away from engine, as required, until correct tension is obtained asshown. Belt should depress 1/4in. (6 mm).

76094

ab

a - Check Pointb - Alternator Pivot Bolt

b. After obtaining correct tension, securely retighten alternator brace attaching boltsand alternator mounting bolts.

2. If a new drive belt has been installed, recheck belt tension after running for five minutes.

Troubleshooting Tests (Alternator on Engine)

Use the following tests in conjunction with the “Troubleshooting” in Section 1C. Before pro-ceeding with the tests, however, perform the following checks to eliminate possible problemareas. Also observe “Precautions,” earlier in this section, to prevent damage to alternatorsystem.

1. If problem is an undercharged battery, check to ensure that undercharged condition hasnot been caused by excessive accessory current draw or by accessories which haveaccidentally been left on. Also, check that undercharged condition has not been causedby running engine at too low a speed for extended periods of time.

2. Check physical condition and state of charge of battery, as outlined in “Battery - Storage”in Section 4A. Battery MUST BE at least 75% (1.230 specific gravity) of fully chargedto obtain valid results in the following tests. If not, charge battery before testing system.

3. Inspect entire alternator system wiring for defects. Check all connections for tightnessand cleanliness, particularly battery cable clamps and battery terminals.

4. Check alternator drive belt for excessive wear, cracks, fraying and glazed surfaces andreplace if necessary. Also, check drive belt tension and adjust if necessary, as outlinedunder “Drive Belt Tension Adjustment.”


Page 4C-8 90-861329--1 MARCH 1999

Circuitry TestPerform the following tests, using a 0-20 volt DC voltmeter, to check that all of the circuitsbetween the alternator and the other components within the alternator system are in goodcondition.

OUTPUT CIRCUIT

1. Connect positive (+) voltmeter lead to alternator output terminal and negative (–) leadto a ground terminal on alternator.

2. Wiggle engine wiring harness while observing voltmeter. Meter should indicate approxi-mate battery voltage and should not vary. If no reading is obtained, or if reading varies,check alternator output circuit for loose or dirty connections or damaged wiring.

72784

e

a

b

c

d

a - Output Wire - ORANGEb - Excitation Wire - PURPLEc - Sensing Wire - RED/PURPLEd - Voltmeter (0-20 Volts)e - Ground

EXCITATION CIRCUIT

1. Connect positive (+) voltmeter lead to tie strap terminal on alternator and negative (–)lead to a ground terminal on alternator (Test 1).

2. Turn ignition switch to ON position and note voltmeter reading. Reading should be 1.3to 2.5 volts.

3. If no reading is obtained, an opening exists in alternator excitation lead or in excitationcircuit of regulator. Unplug PURPLE lead from regulator. Connect positive voltmeterlead to PURPLE lead and negative voltmeter leads to ground (Test 2). If voltmeter nowindicates approximate battery voltage, voltage regulator is defective and must be re-placed. If no voltage is indicated, check excitation circuit for loose or dirty connectionsor damaged wiring.

4. If reading is between .75 and 1.1 volts, rotor field circuit probably is shorted or grounded.Disassemble alternator and test rotor as outlined under “Alternator Repair,” following.


90-861329--1 MARCH 1999 Page 4C-9

5. If reading is between 6.0 and 7.0 volts, rotor field circuit probably is open. Removeregulator and inspect for worn brushes or dirty slip rings. Replace brushes if less than1/4 in. (6 mm) long. If brushes and slip rings are in good condition, disassemble andperform rotor test as outlined under “Component Testing - Rotor” following.

72784

e

a

b

c

d

a - Excitation Wire - PURPLEb - Sensing Wire - RED/PURPLEc - Tie Bard - Voltmeter (0-20 Volts)e - Ground

SENSING CIRCUIT

1. Unplug RED/PURPLE lead from voltage regulator.

2. Connect positive (+) voltmeter lead to RED/PURPLE lead and negative (–) voltmeterlead to ground terminal.

3. Voltmeter should indicate battery voltage. If battery voltage is not present, check sens-ing circuit RED/PURPLE lead for loose or dirty connection or damaged wiring.

72786

e

a

b c

d



Page 4C-10 90-861329--1 MARCH 1999

Current Output TestPerform this test to check if alternator is capable of producing rated current output, usinga 0-50 amp DC ammeter.

WARNINGBe sure that engine compartment is well-ventilated and that there are no gasolinevapors present (during the test) to prevent the possibility of an explosion and/or afire, should a spark occur.

1. Disconnect negative (–) battery cable from battery.

2. Disconnect ORANGE lead from alternator output terminal and connect ammeter inseries between lead and output terminal. Connect positive (+) side of ammeter towardoutput terminal.

3. Reconnect negative battery cable.

4. Remove coil wire from distributor cap tower and ground it to block. Turn on all accesso-ries and crank engine over with starter motor for 15-20 seconds.

5. Turn off accessories and reinstall coil wire. Start engine and adjust engine speed to1500-2000 rpm. Quickly observe ammeter. Reading should be at least 30 amps.

6. If reading is low, stop engine and connect a jumper wire between alternator output termi-nal and regulator terminal. Repeat Steps 4 and 5.

7. If reading is now within specifications, diodes are faulty. Disassemble alternator andreplace rectifier as explained under “Alternator Repair,” following, to determine if faultis in regulator or alternator.

8. If reading is still low with jumper wire connected, perform “Voltage Output Test,” follow-ing, to determine if fault is in regulator or alternator.

72787

b

a

cd

e

f

a - Output Wire - ORANGEb - Ammeter (0-50 Amps)c - Jumper Leadd - Regulator Leade - Groundf - Output Lead (Orange)


90-861329--1 MARCH 1999 Page 4C-11

Voltage Output TestPerform this test to determine if voltage regulator is operating correctly, using a 0-20 volt DCvoltmeter.

IMPORTANT: Battery MUST BE fully charged (1.260 or above specific gravity) toobtain proper voltage reading in this test. If necessary, charge battery with a batterycharger or allow engine to run a sufficient length of time to fully charge battery beforetaking reading.

1. Connect positive (+) voltmeter lead to positive (RED) battery terminal and negative (–)voltmeter lead to negative (BLACK) terminal.

2. Start engine and run at fast idle until engine reaches normal operating temperature.Adjust engine speed to 1500-2000 rpm and observe voltmeter for highest reading.Reading should be between 13.9 and 14.7 volts.

3. If reading is high, check for a loose or dirty regulator ground lead connection. If connec-tion is good (and sensing circuit checked out good in “Circuitry Test”), voltage regulatoris faulty and must be replaced. Be sure to disconnect battery cables before attemptingto remove regulator.

72788

b

a

c

de


WARNINGBe sure that engine compartment is well-ventilated and that there are no gasolinevapors present (during the next steps) to prevent the possibility of an explosionand/or fire, should a spark occur.

CAUTIONDO NOT allow tie jumper wire to contact alternator end frame (in next step), as recti-fier and diode assembly may be damaged.

4. Remove four nuts holding excitation and sensing wires and Phillips screw. Removeregulator cover and install wires and nuts for testing. Connect a jumper wire from theground stud to the brush terminal on the lower right- hand side of the brush assembly.Restart engine and gradually increase engine speed to 1500 rpm while observingvoltmeter. DO NOT allow voltage to exceed 16 volts.


Page 4C-12 90-861329--1 MARCH 1999

5. If a voltmeter reading of 14.5 volts or above is now obtained, voltage regulator is faultyand must be replaced. If voltmeter reading is below 14.5 volts, inspect brushes and sliprings for wear, dirt or damage. If brushes and slip rings are good, alternator is faultyinternally. Disassemble alternator and test components, as outlined under “AlternatorRepair,” following.

72971

d

a

b c

a - Groundb - Brush/Regulator Assemblyc - Brush Terminald - Jumper Wire

Alternator Repair

Removal1. Disconnect negative (–) battery cable from battery.

2. Disconnect wiring harness from alternator.

3. Remove alternator brace-to-alternator attaching bolt, washer(s) and spacer (if used).

4. Loosen alternator brace-to-engine attaching bolt and alternator mounting bolt, thenpivot alternator inward and remove alternator drive belt.

5. Remove alternator mounting bolt, washers (if used), spacer and nut, and removealternator.


90-861329--1 MARCH 1999 Page 4C-13

Exploded View

72276

��

��

��

��

��

��

��

��

�

�

�

�

�

��

��

��

��

�

��

��

��

��

�

��

��

�

�

�

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1 - Screws (3)2 - Nut (9)3 - Flat Washer (4)4 - Sensing Wire (RED / PURPLE)5 - Excitation Wire (PURPLE)6 - Cover7 - Tie Strap8 - Rubber Gasket9 - Condenser

10 - Insulator11 - Bolt (4)12 - End Frame (Rear)13 - Cap (2)14 - Brush / Regulator Assembly15 - Rectifier Assembly

16 - Flat Washer17 - Screw18 - Stator19 - Rotor And Slip Ring20 - Retaining Plate21 - Front Bearing22 - End Frame (Front)23 - Screw (3)24 - Fan Spacer25 - Fan26 - Pulley Spacer27 - Pulley28 - Lockwasher29 - Nut


Page 4C-14 90-861329--1 MARCH 1999

DisassemblyIMPORTANT: The following instructions are for complete disassembly and overhaulof the alternator. In many cases, however, complete disassembly of alternator is notrequired and, in those cases, it is necessary only to perform the operations requiredto repair or replace the faulty part.

1. Mount alternator in a vise so that rear end frame is facing you.

2. Disconnect regulator leads from terminals on rear end frame. Remove four nuts, Phillipshead screw and two regulator leads. Then pull regulator cover away from rear endframe.

72963

bd c

a

a - Regulator Leadsb - Nuts (4)c - Phillips Head Screwd - Regulator Cover

3. Remove stud cover insulator, two nuts and tie strap from brush/regulator assembly.

4. Remove two brush/regulator attaching screws and remove brush/regulator assembly.

72823a

b

c

d

a - Screwsb - Brush/Regulator Assemblyc - Stud Cover Insulatord - Tie Strap

5. Scribe a mark on rear end frame, stator and front end frame to ensure properreassembly later.

6. Remove four screws which secure end frames and stator together.


90-861329--1 MARCH 1999 Page 4C-15

IMPORTANT: DO NOT insert screwdriver blades more than 1/16in. (1.5 mm) into open-ings (in next step), as stator windings may be damaged.

7. Separate rear end frame and stator assembly from front end frame and rotor assemblyusing two thin blade screwdrivers (positioned 180 degrees apart from one another) atthe locations shown. Use the two slots shown to initially separate units.

72824

b

e

d

a

c

a

a - DO NOT Insert Screwdriver Blades More Than 1/16in. (1.5 mm) Into Slotsb - Rear End Framec - Statord - Front End Framee - Scribe Marks

8. Place rear end frame and stator assembly on the bench with stator downward. Be surethat bench is clean and free of metal chips. Remove nuts, washers, insulators and con-denser from output and ground studs.

9. Turn end frame over (stator upward) and remove one Phillips head screw which securesrectifiers to end frame.

72826

a

b

a - Rectifier Assemblyb - Phillips Head Screw

10. Separate stator and rectifier assembly from rear end frame using screwdriver slots.


Page 4C-16 90-861329--1 MARCH 1999

11. Unsolder the three stator leads from the rectifier heat sink. Place a needle nose plierson diode terminal between solder joint and diode body to help prevent heat damage todiodes. Unsolder joints as quickly as possible and allow diode terminal to cool beforeremoving pliers.

72827

a

b

b

a - Heat Sinkb - Stator Leads (3)

IMPORTANT: With alternator disassembled to this point, stator, rectifier, diodes, androtor may be tested, as explained under “Component Testing,” following.

IMPORTANT: DO NOT clamp vise on rotor pole pieces when removing pulley nut (innext step), as pole pieces may be distorted.

12. Remove pulley retaining nut by clamping pulley in a vise (using an oversize V-belt orprotective jaws to protect pulley) and turning nut counterclockwise with a 7/8 in. wrench.Remove lockwasher and slide pulley and fan from shaft. If pulley is difficult to remove,it may be necessary to use a universal puller.

72828

b

a

a - 7/8 in. Wrenchb - Over-Sized V-Belt To Protect Pulley


90-861329--1 MARCH 1999 Page 4C-17

13. Remove the three Phillips head screws and lockwashers which secure the front bearingretaining plate.

72829

b

a

a - Phillips Head Screws and Lockwashersb - Front Bearing Retaining Plate

14. Remove front bearing from front end frame using an arbor press and a suitable sizemandrel. Discard bearing.

72830

a

b

c

a - Pressb - Mandrelc - Bearing

15. If rotor slip rings or rear bearing requires replacement, entire rotor must be replaced.Parts cannot be purchased separately.


Page 4C-18 90-861329--1 MARCH 1999

Cleaning and Inspection1. Clean all parts with a clean, soft cloth. DO NOT use solvent, or electrical components

may be damaged.

2. Inspect the following parts for wear and damage:

a. Brush/regulator assembly - inspect for cracked casing, damaged brush leads,poor brush lead solder connections, weak or broken brush springs or worn brushes.Replace brush set if brushes are less than 1/4in. (6 mm) long.

b. Rotor - inspect for stripped threads, scuffed pole piece fingers or damaged bearingsurfaces (because of bearing turning on shaft).

c. Rotor-slip rings - clean slip rings with 400 grain (or finer) polishing cloth while spin-ning rotor in a lathe. Blow off dust with compressed air. Inspect slip rings for grooves,pits, flat spots or out-of-round [.002in. (0.051 mm) maximum] and replace rotor, ifpresent.

d. Rotor shaft and front end bearings - inspect for damaged seals, lack of lubrica-tion, discoloration (from overheating) and excessive side or end play. Bearingshould turn freely without binding or evidence of rough spots.

e. Stator - inspect for damaged insulation or wires; also inspect insulating enamel forheat discoloration, as this is usually a sign of a shorted or grounded winding or ashorted diode.

f. Front and rear end frames - inspect for cracks, distortion, stripped threads or wearin bearing bore (from bearing outer race spinning in bore). End frame(s) MUST BEreplaced, if bearing has spun. Also, inspect bearing retainer recess in front endframe for damage.

g. Fan - inspect for cracked or bent fins, broken welds (bi-rotational fan only) or wornmounting hole (from fan spinning on shaft).

h. Pulley - inspect pulley mounting bore end for wear. Inspect drive surface of pulleysheaves for trueness, excessive wear, grooves, pits, nicks and corrosion. Repairdamaged surfaces, if possible, with a fine file and a wire brush or replace pulley, ifbeyond repair. Drive surfaces MUST BE perfectly true and smooth or drive belt wearwill be greatly accelerated.


90-861329--1 MARCH 1999 Page 4C-19

Component TestingROTOR

1. Test rotor field circuit for opens, shorts or high resistance (Test 1), using an ohmmeter(set on R x1 scale), as follows:

72831

a b

Testing Rotor Field Circuita - Test 1b - Test 2

a. Connect one ohmmeter lead to each slip ring.

b. Ohmmeter reading should be 4.2 to 5.5 ohms with rotor at room temperature70-80°F (21-26°C).

c. If reading is high or infinite (no meter movement), high resistance or an open existsin the field circuit. Check for poor connections between field winding leads and slipring terminals. If cause for open or high resistance cannot be found, connect ohm-meter directly to slip ring terminals. If correct reading is now obtained, or if readingis still high or infinite, replace complete rotor assembly.

d. If reading is low, a short exists in the field circuit. Inspect slip rings to be sure thatthey are not bent and touching outer slip ring. Also, be sure that excess solder is notshorting terminals to aft slip ring. If cause for short cannot be found, unsolder fieldwinding leads from slip ring terminals and connect ohmmeter directly to leads. If cor-rect reading is now obtained, or if reading is still low, slip rings and rotor field windingsare shorted, and complete rotor assembly must be replaced.

73112

b

a

c

d

a - Field Winding Leadsb - Slip Ringsc - Rotor Shaftd - Pole Pieces


Page 4C-20 90-861329--1 MARCH 1999

2. Test rotor field circuit for grounds (Test 2), using an ohmmeter (set on R x1 scale) asfollows:

a. Connect one lead of ohmmeter to either slip ring and the other lead to rotor shaft orpole pieces.

b. Meter should indicate no continuity (meter should not move).

c. If continuity does exist, complete rotor assembly must be replaced.

IMPORTANT: If alternator has output at low speeds, but no output at high speeds,rotor field winding may be shorting or grounding out, due to centrifugal force.Replace rotor if all other electrical components test good.

STATOR

IMPORTANT: Stator leads MUST BE disconnected from rectifier for this test.

1. Test stator for grounds (Test 1), using an ohmmeter (set on R x1 scale) as follows:

a. Connect one lead of ohmmeter to one of the stator leads and the other lead to statorframe. Be sure that lead makes good contact with frame.

b. Meter should indicate no continuity (meter should not move). If continuity does exist,stator is grounded and must be replaced.

2. Test for opens in stator (Test 2), using an ohmmeter (set on R x1 scale) as follows:

a. Connect ohmmeter between each pair of stator windings (three different ways).

b. Continuity should be present in all three cases (meter should move). If it does not,one or more of the windings are open and stator must be replaced.

72833

a b b b

Testing Statora - Test 1b - Test 2

3. A short in the stator is difficult to detect without special equipment, because of the lowwindings resistance. If all other electrical components test out good, and alternator failsto produce rated output, stator probably is shorted and should be replaced. Also,examine stator for heat discoloration, as this usually is a sure sign of a short.


90-861329--1 MARCH 1999 Page 4C-21

RECTIFIER AND DIODE ASSEMBLY

NOTE: Failure of any component in tests following will require replacement of entire rectifierassembly.

NEGATIVE (–) RECTIFIER

IMPORTANT: Rectifier MUST BE disconnected from stator for this test.

CAUTIONDO NOT use a test instrument with more than a 12 volt source (in the following test),as rectifier may be damaged.

1. Connect one lead of an ohmmeter (set on R x1 scale) to negative (–) rectifier heat sinkand the other lead to one of the rectifier terminals. Note the reading.

2. Reverse leads and again note reading.

3. Meter should indicate a high or infinite resistance (no meter movement) when con-nected one way and a low reading when connected the other. If both readings are highor infinite, rectifier is open. If both readings are low, rectifier is shorted.

4. Repeat Steps 1 through 3 for two other rectifiers in heat sink.

5. Replace assembly if any of the rectifiers is shorted or open.

72147

b

a

c

a - Heat Sinkb - Rectifier Terminalc - Test These Two Rectifiers in Same Manner

POSITIVE (+) RECTIFIER AND DIODES

CAUTIONDO NOT use a test instrument with more than a 12 volt source (in the following test),as rectifier may be damaged.

1. Connect one lead of an ohmmeter (set on R x1 scale) to 1/4in. stud on positive (+)rectifier heat sink and the other lead to one of the rectifier terminals. Note the meterreading.



Page 4C-22 90-861329--1 MARCH 1999

3. Meter should indicate a high or infinite resistance (no meter movement) when con-nected one way and a low reading when connected the other. If both readings are highor infinite, rectifier is open. If both readings are low, rectifier is shorted.

4. Repeat Steps 1 through 3 for two other rectifiers in heat sink.

72834

b

a

c

a - Studb - Rectifier Terminalc - Repeat Test Between These Terminals And Stud

5. Replace assembly if any one of the rectifiers is shorted or open.

6. Connect one lead of an ohmmeter (set on R x1) to the common side of the diode andthe other lead to the other side, of one of the three diodes.

72148

a

b

a - Common Side of Diode Circuit Boardb - Repeat Test for These Two Diodes


8. Meter should indicate a high or infinite resistance (no meter movement) whenconnected one way and a low reading when connected the other. If both readings arehigh or infinite, diode is open. If both readings are low, diode is shorted.

9. Repeat Steps 6 through 8 for the other two diodes.

10. Replace rectifier assembly if any one of the diodes is shorted or open.


90-861329--1 MARCH 1999 Page 4C-23

CONDENSER

1. Using magneto analyzer and accompanying instructions, perform the followingcondenser tests:

a. Condenser Capacity Test (must be .5 mfd).

b. Condenser Short or Leakage Test.

c. Condenser Series Resistance Test.

2. Replace condenser if test results are not within specifications.

Reassembly1. Install new front bearing into front end frame bearing bore using an arbor press. If neces-

sary, use a bearing driver that contacts outer race only.

72835

b

a

a - Pressb - Mandrel

2. Install front bearing retaining plate using three Phillips head screws and lockwashers.

72829

a

b

a - Phillips Head Screws and Lockwashersb - Front Bearing Retaining Plate

3. Slide front end frame over rotor.


Page 4C-24 90-861329--1 MARCH 1999

IMPORTANT: DO NOT clamp vise on rotor pole pieces when tightening pulley nut (innext step), or pole pieces may be distorted.

4. Slide fan spacer onto rotor shaft. Install fan, pulley, lockwasher and nut on shaft. Clamppulley in a vise, using protective jaws or an old oversize V-belt to protect pulley, andtorque nut to specifications. Tighten vise only enough to allow tightening of nut, asexcessive tightening may distort pulley.

5. Assemble stator to rectifier by soldering the three leads to the three rectifier terminals.

72826

a

a - Stator Lead Connections

NOTE: Be sure to connect leads to their original positions.

6. Install assembled stator and rectifier assembly into rear end frame, aligning scribemarks on each (scribed during disassembly), and install Phillips head screw and washerto retain.

IMPORTANT: The insulating washers MUST BE installed as shown or damage to thealternator will result.

7. Position stator down with rear end frame up and reinstall insulators, nuts and condenser.

72561

b

a

cb

a - Insulators (3)b - Nuts (5) (One Removed)c - Condenser


90-861329--1 MARCH 1999 Page 4C-25

8. Position rear end frame and stator assembly over front end frame and rotor assemblyand align scribe marks on each (scribed during disassembly). Hand-press end framestogether, then install four screws. Tighten screws securely.

72561

d

a

bc

e

a - Rear End Frameb - Statorc - Front End Framed - Scribe Markse - Insert Screws (4) (Two Hidden)

9. Depress brushes flush with top of brush holder and insert a #54 drill bit or smaller(.050in.) into hole in brush holder to hold brushes compressed during reassembly.

72836a

a - Drill Bit

NOTE: Shown with rubber gasket removed for clarity.


Page 4C-26 90-861329--1 MARCH 1999

10. Install brush/regulator assembly in rear end frame cavity and secure with two mountingscrews, as shown. Tighten screws securely. Remove drill bit to release brushes againstslip rings.

72837

a

b

a - Brush/Regulator Assemblyb - Mounting Screws

11. Install tie strap to rectifier stud and stud on brush/rectifier assembly. Tighten nutssecurely.

72823

b

a

a - Studsb - Tie Strap


90-861329--1 MARCH 1999 Page 4C-27

12. Install cover with one Phillips head screw and two nuts. Install two leads with nuts.

72963

ab

c

a - Phillips Head Screwb - Nuts (4)c - Leads

13. Install insulator caps.

72078

a

a - Insulator Caps


Page 4C-28 90-861329--1 MARCH 1999

Installation

1. Position alternator in mounting bracket and install mounting bolt, washers (if used),spacer and nut. Place washers (if used), on each side of spacer. DO NOT tightensecurely at this time.

2. Fasten alternator brace to alternator with bolt, washers and spacer (if used). DO NOTtighten bolt at this time.

3. Position alternator drive belt on pulleys and adjust tension as explained under “DriveBelt Tension Adjustment.”

4. Reconnect wiring harness to alternator and negative battery cable to battery.

72838

d

a

b

c

a - Excitation Lead - PURPLEb - Sensing Lead - RED/PURPLEc - Ground Lead - BLACKd - Output Lead - ORANGE

IMPORTANT: Alternators used on MerCruiser engines ARE NOT equipped with anisolation diode.

CAUTIONFollow battery isolator manufacturer’s instructions for wire gauge. Battery isolatorinstallation must conform to BIA Low Voltage Wiring Standard No. 125-79.

NOTE: MerCruiser engines equipped with a 3-wire, belt driven alternator can use a batteryisolator.


90-861329--1 MARCH 1999 Page 4C-29

Batteries

Battery CablesSelect proper size positive (+) and negative (–) battery cables, using chart. Battery shouldbe located as close to engine as possible.

IMPORTANT: Terminals must be soldered to cable ends to ensure good electricalcontact. Use electrical grade (resin flux) solder only. Do not use acid flux solder asit may cause corrosion and a subsequent failure.

Cable Length Cable Gauge

Up to 3 - 1/2 ft (1.1m) 4 (25 mm2)

3-1/2 - 6 ft (1.1-1.8m) 2 (35mm2)

6 ft - 7-1/2 ft (1.8-2.3m) 1 (50mm2)

7-1/2 - 9-1/2 ft (2.3-2.9m) 0 (50mm2)

9-1/2 - 12 ft (2.9-3.7m) 00 (70mm2)

12 - 15 ft (3.7-4.6m) 000 (95mm2)

15 - 19 ft (4.6-5.8m) 0000 (120m2)


Page 4C-30 90-861329--1 MARCH 1999


Identification

72078

a

b

c





Specifications

Description Specification

Excitation Circuit 1.3-2.5 Volts

Current Output 50 Amp Minimum

Voltage Output 13.9-14.7 Volts

Condenser Capacity .5 MFD

Minimum Brush Length 1/4in. (6mm)


90-861329--1 MARCH 1999 Page 4C-31

Tools


Bearing Removal and Installation Kit 91-31229A7

Magneto Analyzer 91-76032

Universal Puller Plate 91-37241

Multi-Meter/DVA Tester 91-99750A1

Ammeter (0-50 Amps) Obtain Locally






End Frame Screws 55 6.5

Brush Setscrews 18 1.5

Regulator Mounting Screws 43 4.5

Regulator Leads 25 2.5

Ground Terminal Nut 25 2.5

Pulley Nut 42 58

Alternator Brace to Alternator 192 28

Alternator Brace to Block 30 40

Alternator to Mounting Bracket 35 48

Alternator Mounting Bracket 30 41

V-Belt Tension (Note) Depress 1/2in. (13mm)

NOTE: Depress belt with thumb at midway point between circulating pump pulley andalternator.


Page 4C-32 90-861329--1 MARCH 1999

Battery Isolator Diagram

72934

a b

c

d

e

f

c

d

g

f

h

�

��

a - Circuit Breakerb - Harness Connectorc - Alternatord - Startere - Cranking Batteryf - Ground Studg - Auxiliary Batteryh - Isolator

1 - Disconnect Orange Wire From Alternator “Batt” Terminal. Splice SufficientGauge Wire To The Orange Wire And Connect As Shown.

2 - 8 Gauge Minimum


90-861329--1 MARCH 1999 Page 4C-33


Identification

72078

b

c

a





Specifications

Description Specification

Excitation Circuit 1.3 to 2.5 Volts

Current Output 60 Amp. Min.

Voltage Output 13.9 to 14.7 Volts

Min. Brush Length 1/4in. (6 mm)


Page 4C-34 90-861329--1 MARCH 1999

Tools


Bearing Removal and Installation Kit 91-31229A7

Universal Puller Plate 91-37241

Multi-Meter/DVA Tester 91-99750A1

Ammeter (0-100 Amp) Obtain Locally






End Frame Screws 55 5.5

Brush Setscrews 18 1.5

Regulator Mounting Screws 42 4.2

Regulator Leads 25 2.5

Ground Terminal Nut 25 2.5

Pulley Nut 42 57

Alternator to Mounting Bracket 35 48

Alternator Mounting Bracket 30 41

Belt Tension See Note

NOTE: Belt deflection is to be measured on the belt at the location that has the longestdistance between two (2) pulleys. Normally this location is between the power steeringpump and the belt adjustment pulley. This location will be different on engines with closedcooling or models without power steering.

NOTE: Depress belt with thumb at midway point between circulating pump pulley andalternator.


90-861329--1 MARCH 1999 Page 4C-35

Exploded View

72276

��

��

��

��

��

��

��

��

�

�

�

�

�

��

��

��

��

�

��

��

��

��

�

��

��

�

�

�

��

1 - Screws (3)2 - Nut (9)3 - Flat Washer (4)4 - Sensing Wire (RED / PURPLE)5 - Excitation Wire (PURPLE)6 - Cover7 - Tie Strap8 - Rubber Gasket9 - Condenser

10 - Insulator11 - Bolt (4)12 - End Frame (Rear)13 - Cap (2)14 - Brush / Regulator Assembly15 - Rectifier Assembly

16 - Flat Washer17 - Screw18 - Stator19 - Rotor And Slip Ring20 - Retaining Plate21 - Front Bearing22 - End Frame (Front)23 - Screw (3)24 - Fan Spacer25 - Fan26 - Pulley Spacer27 - Pulley28 - Lockwasher29 - Nut


Page 4C-36 90-861329--1 MARCH 1999


4D

INSTRUMENTATIONSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 4D-1

ELECTRICAL SYSTEMSection 4D - Instrumentation

Table of Contents

Identification 4D-2. . . . . . . . . . . . . . . . . . . . . . . . . . Special Information 4D-3. . . . . . . . . . . . . . . . . . . .

Lighting Options 4D-3. . . . . . . . . . . . . . . . . . . . Gauges 4D-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Oil, Fuel and Temperature 4D-5. . . . . . . . . . . Battery Gauge 4D-7. . . . . . . . . . . . . . . . . . . . . Cruiselog Meter 4D-8. . . . . . . . . . . . . . . . . . . . Vacuum Gauge 4D-8. . . . . . . . . . . . . . . . . . . . . Speedometer 4D-9. . . . . . . . . . . . . . . . . . . . . . Tachometer 4D-9. . . . . . . . . . . . . . . . . . . . . . . . Gauge Replacement 4D-9. . . . . . . . . . . . . . . .

Senders 4D-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Pressure 4D-10. . . . . . . . . . . . . . . . . . . . . . Water Temperature Sender 4D-11. . . . . . . . .

Fuel Tank Sender 4D-14. . . . . . . . . . . . . . . . . . . . Flange Type 4D-14. . . . . . . . . . . . . . . . . . . . . . Capsule Type 4D-15. . . . . . . . . . . . . . . . . . . . .

Switches 4D-16. . . . . . . . . . . . . . . . . . . . . . . . . . . . Ignition Key Switch 4D-16. . . . . . . . . . . . . . . .

Audio Warning System 4D-17. . . . . . . . . . . . . . . . Buzzer 4D-17. . . . . . . . . . . . . . . . . . . . . . . . . . . Oil Pressure Switch 4D-18. . . . . . . . . . . . . . . . Water Temperature Switch 4D-18. . . . . . . . . .

INSTRUMENTATION SERVICE MANUAL NUMBER 26

Page 4D-2 90-861329--1 MARCH 1999

Identification

One of three distinct lines (Series) of Quicksilver gauges may be installed (if equipped withQuicksilver gauges). Aside from different gauge face appearances and styling, the back ofthe gauges and wiring connections are different as shown.

72746

Back of Commodore and International Series Gauge - Typical

72965

Back of QSI Series Gauge - Typical


90-861329--1 MARCH 1999 Page 4D-3

Special Information

Lighting Options

COMMODORE AND INTERNATIONAL SERIES

These gauges may be wired so that the illumination lighting is provided from the ignitionswitch or a separate instrumentation lighting switch.

By removing contact strip “I” from between + terminal and the screw as shown following, andsupplying a separate +12 V power supply to the screw connection, illumination lights canbe operated independent of ignition switch.

72966

b

a

c

Ignition Switch Lighting Circuita - +12 V Power Supply From Ignition Switchb - Contact Strip “I”c - Screw Connection

72967b

a

c

Separate Instrumentation Lighting Circuit Wiringa - 12 Volt Power Supply From Separate Instrumentation Lighting Circuitb - Contact Strip “I” - Removedc - Screw Connection


Page 4D-4 90-861329--1 MARCH 1999

QSI SERIES

These gauges are equipped with optional illumination lighting. Light bulb socket can beremoved and contacts can be aligned to be used with ignition switch lighting circuit +12 Vor separate instrumentation lighting circuit LT.

IMPORTANT: Light socket must be removed from gauge and turned counterclock-wise (facing back of gauge) when adjusting to desired setting. Turning socket whilestill installed in gauge could result in damage to gauge or socket.

NOTE: For different lighting effects, colored sleeves are available through the QuicksilverAccessories and can be assembled to the bulb.

72968

a

Ignition Switch Lighting Circuit Positiona - +12 V Power Supply From Ignition Switch

72969

b

a

Separate Instrumentation Lighting Circuit Positiona - +12 V Power Supply From Ignition Switchb - +12 V Power Supply From Separate Instrumentation Lighting Circuit


90-861329--1 MARCH 1999 Page 4D-5

Gauges

Oil, Fuel and TemperatureIMPORTANT: If testing proves gauge to be defective, it must be replaced as there isno repair available.

TESTING

1. Turn ignition switch to OFF.

2. Remove wire from terminal S (SEND).

72965a

Typicala - Sender Terminal

3. Turn ignition switch to RUN. Gauge being tested must be at position A.

72747

Typical Position A

4. Turn ignition switch to OFF.


Page 4D-6 90-861329--1 MARCH 1999

5. Connect jumper wire from terminal G (GND) to terminal S (SEND).

72748

Typical

6. Turn ignition switch to RUN.

7. Indicator needle of gauge being tested must read at position B. If not, replace gauge.

72749

Typical Position B


90-861329--1 MARCH 1999 Page 4D-7

Battery Gauge

TESTING

1. Remove cables from battery and fully charge battery.

2. Connect negative (–) jumper lead from battery to gauge terminal G (GND).

3. Connect positive (+) jumper lead from battery to gauge terminal I or +12 V.

72750

Typical

4. Check gauge reading; if not as shown replace gauge.

72751

Typical


Page 4D-8 90-861329--1 MARCH 1999

Cruiselog Meter

TESTING

1. Connect jumper wire from negative (–) battery terminal to negative (–) gauge terminal.

2. Connect jumper wire from positive (+) battery terminal to positive (+) gauge terminal.

72752

3. Observe gauge run indicator. If indicator is turning, gauge is operable; if not, replacegauge.

72753

a

a - Indicator

Vacuum Gauge

TESTING

1. Disconnect vacuum hose from engine. Connect service vacuum gauge to engine andrecord engine vacuum readings at idle, 1000, 2000 and 3000 rpm. Reconnect vacuumhose and compare vacuum gauge readings (at specified rpm) with service gauge read-ings. Readings should be within 3 inches of vacuum of each other.

IMPORTANT: Make sure that vacuum hose between gauge and engine is not leakingand that all connections are tight.


90-861329--1 MARCH 1999 Page 4D-9

Speedometer

TESTING

IMPORTANT: When testing speedometer gauge for accuracy, the air supply used forthe test must be regulated to the specified air pressure. Do not apply excessive airpressure to speedometer gauge.

1. Apply air pressure directly to speedometer gauge (specified in chart) and note gaugereading. Light tapping of pressure gauge is required during accuracy check.

2. If gauge readings are not within specifications, gauge is defective.

CALIBRATION CHART

Air Pressure Gauge psi Speedometer Gauge MPH (km/Hr)

5.3 20 + 1 (32 + 1.6)

27.8 45 + 1 (72 + 1.6)

Tachometer

TESTING

1. Connect a service tachometer to engine and compare readings.

2. Replace if not within specifications.

Tachometer Type Allowable Range

6000 rpm + 150 rpm

8000 rpm + 200 rpm

Gauge Replacement1. Disconnect battery cables from battery.

2. Remove wires from back of gauge.

3. Remove hoses (vacuum, speedometer gauge).

4. Disconnect light socket.

5. Remove holding strap and remove gauge.

6. Position gauge assembly in appropriate mounting hole.

7. Install holding strap and nuts. Tighten nuts evenly and securely.

IMPORTANT: Do not distort case or bracket by overtightening.

8. Connect ground (BLACK) wire to ground terminal, if gauge is not mounted in metalpanel.

9. Connect other wires to gauge as shown in SECTION 4E.

10. Connect hoses (vacuum, speedometer gauges).

11. Install gauge light socket.

12. Coat all terminals with Quicksilver Liquid Neoprene.

13. Reconnect battery cables to battery.


Page 4D-10 90-861329--1 MARCH 1999

Senders

Oil Pressure

TESTING

IMPORTANT: Use following test procedure for checking accuracy of oil pressuresender only. If oil pressure gauge indicates zero oil pressure, refer to SECTION 4C“Troubleshooting.”

1. Remove wire from sender terminal.

2. Connect ohmmeter between sender terminal and sender case. Check ohms readingwithout engine running (zero pressure), then check reading with engine running. Com-pare oil pressure and ohms readings as shown in following chart:

72754

b

a

c

d

a - Positive Leadb - Negative Leadc - Wire Removedd - Oil Pressure Sender

Ohms ReadingOil Pressure (psi)

Single Dual

0 227-257 113.5-128.5

20 142-162.5 71-81.3

40 91.7-113.6 45.9-56.8

80 9-49 11-24.5

DUAL STATION SENDER IDENTIFICATION

Sender will have 3353-AM stamped on hex of sender.


90-861329--1 MARCH 1999 Page 4D-11

Water Temperature SenderThere is no accurate test that can be done without special equipment. Install new sender.

TESTING

1. Connect an ohmmeter between temperature sender terminal (+) and hex (case) forground (–) as shown.

72768

a

b

a - Ohmmeter Leadsb - Water Temperature Sender

WARNINGThe following test involves the use of intense heat. Failure to follow appropriateprocedures or warnings can cause burns which can result in severe personal injury.While performing the following test, observe these general precautions:

• Wear personal protective clothing such as rubber gloves, a non-flammableapron, and eye protection - preferably full face shield or safety glasses.

• The appropriate heat source should only be electric. Heat source should beoperated by a qualified person. Be sure to follow all instructions of themanufacturer of the heat source. The heat source should be checked each timeit is used to be sure it is functioning properly.

• The thermometer used in the test should be a high-temperature thermometerwith a maximum reading of at least 300°F (150°C). Under no circumstancesshould the operator allow temperatures to exceed test specifications.

• Perform test only in a well ventilated area.

• Use a suitable container, such as metal, to hold the water. Avoid use of glasscontainers unless the operator first confirms for himself/herself that the glasscontainer is an appropriate high-temperature vessel.

• Because the components will reach high temperatures DO NOT handle materi-als or components until COMPLETELY cooled.


Page 4D-12 90-861329--1 MARCH 1999

2. Follow these instructions:

a. With ohmmeter connected as outlined and using suitable container, thermometerand heat source, suspend sender with tip in water.

b. Heat water and observe thermometer.

c. As temperature rises ohmmeter readings must be within the ranges specified foreach temperature (see chart below).

d. Turn heat source off. Allow water and components to cool.

NOTE: While water cools you may recheck ohmmeter readings.

72769

b

a

c

de

a - Suitable Containerb - Thermometerc - Heat Sourced - Water Temperature Sendere - Ohmmeter Leads

Water Temperature Ohms Reading

140°F (60°C) 121-147

194°F (90°C) 47-55

212°F (100°C) 36-41

3. Replace sender if ohmmeter readings are other than as shown for each temperature.


90-861329--1 MARCH 1999 Page 4D-13

INSTALLATION

1. Apply Loctite Pipe Sealant with Teflon to threads of temperature sender.

2. Install sender in thermostat housing and tighten securely.

3. Connect TAN wire and coat with liquid neoprene.

a

b

a - TAN Wireb - Water Temperature Sender

4. Refill closed cooling system with approved coolant as outlined in SECTION 6B.

DUAL STATION SENDER IDENTIFICATION

Sender will have 362-BC stamped on hex.


Page 4D-14 90-861329--1 MARCH 1999

Fuel Tank Sender

Flange Type

TESTING

1. Disconnect wire from terminal on sending unit and ground wire from sending unit mount-ing screw.

2. Remove sending unit from fuel tank.

3. Connect ohmmeter between sending unit terminal and sending unit housing.

4. With float arm in FULL position (arm horizontal), ohmmeter should read 30 ohms(+ 5 ohms).

72755b

a

a - Ohmmeter Leadsb - Vertical Float Arm

5. With float arm in EMPTY position (arm vertical) meter should read 240 ohms (+ 5 ohms).Sender is defective if not within specifications.

72756

a

b

a - Ohmmeter Leadsb - Vertical Float Arm


90-861329--1 MARCH 1999 Page 4D-15

Capsule Type

TESTING

1. Disconnect wire from terminal on fuel tank capsule.

2. Remove two screws and remove capsule assembly.

3. Place a magnet under fuel capsule.

4. Connect ohmmeter between fuel capsule terminal and metal portion of capsule housing.

72757c

a

b

a - Ohmmeter Leadsb - Capsule Assemblyc - Magnet

5. Turn magnet counterclockwise until fuel capsule indicator reads EMPTY. Ohmmetershould read 240 ohms (+ 5 ohms).

72758

a

a - Capsule Reading Empty


Page 4D-16 90-861329--1 MARCH 1999

6. Turn magnet clockwise until fuel capsule indicator reads FULL. Ohmmeter should read30 ohms (+ 5 ohms). Fuel capsule is defective if not within specifications.

72759

a

a - Capsule Reading Full

Switches

Ignition Key Switch

TESTING

WARNINGDisconnect battery cables from battery before testing ignition key switch with wiresstill connected to switch.

1. Before testing key switch, check all fuses and/or circuit breakers in electrical circuitwhich could prevent operation of starter.

2. With key switch in OFF position, there should be no continuity between switch terminals.

3. With key switch in RUN position, continuity will exist between switch terminals B to A andB to I. There should be no continuity between terminal C and any other terminals.

4. With key switch in START, continuity will exist between terminals B to A, B to I and B toC.

5. If ignition key switch tests bad, unsolder wire connections and remove switch. Testswitch again, as in Steps 2-5, preceding. If switch tests good, wiring in harness is bad.There should be no continuity between any harness wires with key switch removed.

B

I

AC

Switch Terminal Identification


90-861329--1 MARCH 1999 Page 4D-17

Audio Warning System

Buzzer

WARNINGThe following test involves the use of electricity. Failure to follow appropriate pro-cedures can cause burns or shock which can result in severe personal injury ordeath.

TESTING

1. Turn the ignition switch to the ON position without cranking the engine. The horn willsound if the system is working correctly.

2. If horn does not sound:

a. Connect jumper wires as shown.

b. If horn does not sound, replace it.

3. If horn worked in Step 3:

a. Connect jumper wires as shown.

b. Repeat Step 2.

c. If horn sounds, problem is in TAN/BLUE wire back to engine or switches on engine.

74046


Page 4D-18 90-861329--1 MARCH 1999

Oil Pressure SwitchRefer to SECTION 4E for switch locations. Switch is normally closed.

TESTING

1. Remove wire from sender terminal.

2. Connect continuity meter between sender terminal and sender hex. (Sender shownremoved for clarity.)

72764

3. With engine not running, meter should indicate full continuity.

4. Start engine. With engine running and engine oil pressure above 6 psi (41 kPa), metershould indicate NO continuity.

SWITCH IDENTIFICATION

Switch has 364-AF stamped on hex of sender.

Water Temperature Switch

TESTING

1. Connect an ohmmeter between water temperature switch terminal (+) and hex (case)for ground (–) as shown.

72765

b

a

a - Ohmmeter Leadsb - Water Temperature Switch

2. Switch should read no continuity.


90-861329--1 MARCH 1999 Page 4D-19

WARNINGThe following test involves the use of intense heat. Failure to follow appropriateprocedures or warnings can cause burns which can result in severe personal injury.While performing the following test, observe these general precautions:

• Wear personal protective clothing such as rubber gloves, a non-flammableapron, and eye protection - preferably full face shield or safety glasses.

• The appropriate heat source should only be electric. Heat source should beoperated by a qualified person. Be sure to follow all instructions of themanufacturer of the heat source. The heat source should be checked each timeit is used to be sure it is functioning properly.

• The thermometer used in the test should be a high- temperature thermometerwith a maximum reading of at least 300°F (150°C). Under no circumstancesshould the operator allow temperatures to exceed test specifications.

• Perform test only in a well ventilated area.

• Use a suitable container, such as metal, to hold the sand. Avoid use of glasscontainers unless the operator first confirms for himself/herself that the glasscontainer is an appropriate high-temperature vessel.

• Because the components will reach high temperatures DO NOT handle materi-als or components until COMPLETELY cooled.

WARNINGUse only clean, dry sand such as used for general sandblasting purposes. Use ofsand containing contaminants could result in hazards such as fire, short circuiting,hot-spots, or other hazards.

3. Follow these instructions:

a. With an ohmmeter connected as outlined and using suitable container, thermometerand heat source, suspend sender with tip in sand.

b. Heat sand and observe temperature on thermometer.

72766

a

b

c

de

a - Suitable Containerb - Thermometerc - Heat Sourced - Water Temperature Switche - Ohmmeter Leads


Page 4D-20 90-861329--1 MARCH 1999

c. As temperature rises, switch will close and ohmmeter will indicate continuity. Referto chart below for specifications.

48952 Switch

Opens 150-170°F (60-77°C)

Closes 190-200°F (88-93°C)

87-86080 Switch

Opens 175-195°F (79-91°C)

Closes 215-225°F (102-107°C)

72767

ab

Switch Identificationa - 48952 Switch with Red Mylar Sleeveb - 87-86080 Switch with Black Mylar Sleeve

4. Turn heat source off. Allow sand to cool. Note thermometer reading to ensure switch“opens” up at specified temperature.

5. Replace switch if switch fails to either open or close within the specified temperatures.


90-861329--1 MARCH 1999 Page 4D-21



Page 4D-22 90-861329--1 MARCH 1999


4E

WIRING DIAGRAMSSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 4E-1

ELECTRICAL SYSTEMSection 4E - WIRING DIAGRAMS

Table of Contents

Wiring Diagrams 4E-2. . . . . . . . . . . . . . . . . . . . . . MCM 3.0L Gasoline Engine Wiring Diagrams 4E-2. . . . . . . . . . . . . . . . . . . . . . . . . Quicksilver Instrumentation Wiring Diagram 4E-6. . . . . . . . . . . . . . . . . . . . . . . . . .

Battery Meter Gauge 4E-10. . . . . . . . . . . . . . . . .

Cruiselog 4E-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel Gauge and Sender 4E-11. . . . . . . . . . . . . . . Audio Warning System 4E-12. . . . . . . . . . . . . . . . Water Temperature Gauge 4E-12. . . . . . . . . . . . Oil Pressure Gauge 4E-13. . . . . . . . . . . . . . . . . . Clock 4E-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

WIRING DIAGRAMS SERVICE MANUAL NUMBER 26

Page 4E-2 90-861329--1 MARCH 1999

Wiring Diagrams

MCM 3.0L Gasoline Engine Wiring DiagramsWITHOUT CIRCUIT BREAKER

�

75567

A

C

D

B

BLK = BLACKBLU = BLUEBRN = BROWNGRY = GRAYGRN = GREENORN = ORANGEPNK = PINKPUR = PURPLERED = REDTAN = TAN

WHT = WHITEYEL = YELLOWLIT = LIGHT

DRK = DARK

�

�

�

�

�

�

�

� � �

�

�

�


90-861329--1 MARCH 1999 Page 4E-3

NOTE: Gray lead for use with service tachometer.

A - Ignition Components

1 - Distributor2 - Ignition Coil3 - Shift Cutout Switch

B - Starting Charging and Choke Components

1 - Alternator2 - Electric Choke3 - Ground Stud4 - Starter Motor5 - Starter Slave Solenoid

C - Audio Warning Components

1 - Water Temperature2 - Drive Unit Gear Lube Monitor3 - Oil Pressure Switch

D - Instrumentation Components

1 - Oil Pressure Sender2 - Water Temperature Sender3 - Trim Sender


Page 4E-4 90-861329--1 MARCH 1999

WITH CIRCUIT BREAKER

74101

�

A

C

D

B

�

�

�

�

�

�

�

� � �

�

�

�

�


90-861329--1 MARCH 1999 Page 4E-5


A - Ignition Components

1 - Distributor2 - Ignition Coil3 - Shift Cutout Switch

B - Starting Charging and Choke Components

1 - Alternator2 - Electric Choke3 - Ground Stud4 - Starter Motor5 - Starter Slave Solenoid6 - Circuit Breaker

C - Audio Warning Components

1 - Water Temperature2 - Drive Unit Gear Lube Monitor3 - Oil Pressure Switch

D - Instrumentation Components

1 - Oil Pressure Sender2 - Water Temperature Sender3 - Trim Sender


Page 4E-6 90-861329--1 MARCH 1999

12

3

4

5

6

7

8

10

8 B

LK

BLK

GRAY

PPL

16 BRN–WHT16 BLK

12 R

ED

–PP

L G

XL

16 Y

EL–

RE

D16

BLK

16 B

LK12

YE

L–R

ED

GX

L

16 B

LK16

TA

N16

TA

N–B

LU16

TA

N–B

LU

16 WHT–GRN16 PPL16 PPL16 BLK

8 ORN GXL 8 BLK GXL14 RED–PPL GXL 16 R16 PPL GXL

16 L

T. B

LU10

RE

D G

XL

12 Y

EL–

RE

D G

XL

8 O

RN

GX

L

16 GRY

8 BLK

16 LT. BLU

16 YEL–RED16 BRN–WHT

8 RED–PPL

16 PPL16 TAN–BLU

16 TAN

WH

TW

HT

GR

AY

10 RED GXL 8 RED–PPL ��

��

��

�

�

�

�

�

��


1 - Distributor2 - Ignition Coil3 - Shift Cutout Switch4 - Alternator5 - Starter Motor6 - Starter Slave Solenoid7 - Circuit Breaker8 - Water Temperature9 - Drive Unit Gear Lube Monitor

10 - Oil Pressure Switch11 - Oil Pressure Sender12 - Trim Sender


90-861329--1 MARCH 1999 Page 4E-7



Page 4E-8 90-861329--1 MARCH 1999

Quicksilver Instrumentation Wiring Diagram

SINGLE STATION INSTALLATION - TYPICAL

BLK = BLACKBLU = BLUEBRN = BROWNGRY = GRAYGRN = GREENORN = ORANGEPNK = PINKPUR = PURPLERED = REDTAN = TAN

WHT = WHITEYEL = YELLOWLIT = LIGHT

DRK = DARK

7

J

b

a

c d e

ghf

i

i

i


90-861329--1 MARCH 1999 Page 4E-9

Refer to gauge manufacturer’s instructions for specific connections.

NOTE: 1 Connect Wires Together with Screw and Hex Nut; Apply Liquid Neoprene to Con-nection and Slide Rubber Sleeve over Connection.

NOTE: 2 Power for a Fused Accessory Panel May Be Taken from This Connection. LoadMust Not Exceed 40 Amps. Panel Ground Wire Must Be Connected to Instrument TerminalThat Has an 8-Gauge Black (Ground) Harness Wire Connected to it.

NOTE: 3 Lanyard stop switch lead and neutral safety switch leads must be soldered andcovered with shrink tube for a water proof connection. If an alternate method of connectionis made, verify connection is secure and sealed for a water proof connection.

a - Audio Warning Buzzerb - Tachometerc - Oil Pressured - Water Temperaturee - Battery Meterf - Ignition Switchg - Trim Indicatorh - Read/Observe NOTE 1 and 2.i - Read/Observe NOTE 3.j - To Engine Wiring Harness


Page 4E-10 90-861329--1 MARCH 1999

DUAL STATION USING A NEUTRAL SAFETY SWITCH IN ONLY ONE REMOTE CONTROL

50730

PRIMARY STATION

SECONDARY STATION

a

l

l

k

j

i

j

h

g

g

gf

f

e

ed

d

cb

b

b

b

a - See Note 5b - See Note 4c - Start/Stop Paneld - Water Temperaturee - Oil Pressuref - Tachometerg - Battery Meterh - See Note 2i - See Note 3j - See Note 1k - Extension Harness To Enginel - Fuse

NOTE: 1 BROWN/WHITE wire is taped back at instrument end. If installing on boat that isequipped with MerCruiser sterndrive, BROWN/WHITE wire is connected to the trim senderterminal block. Also can be used for an accessory (limit 5 amps).

NOTE: 2 An accessory fuse panel may be connected at this location. The combined currentdraw of the primary station and secondary station MUST NOT exceed 5 amps.

NOTE: 3 Tape back and insulate with at least four layers of electrical tape.

NOTE: 4 Connect wires together with screw and hex nut. Tighten securely and coat with Liq-uid Neoprene to help control corrosion; when dry, slide neoprene sleeve over connection.

NOTE: 5 To WHT/GRN connection on terminal block at shift plate cutout switch.


90-861329--1 MARCH 1999 Page 4E-11

DUAL STATION USING A NEUTRAL SAFETY SWITCH IN BOTH REMOTE CONTROLS

PRIMARY STATION

SECONDARY STATION

gfedcb

gfed

kj

j b

i

h

a

c

l

b

b

a - See Note 5b - See Note 4c - Start/Stop Paneld - Water Temperaturee - Oil Pressuref - Tachometerg - Battery Meterh - See Note 2i - See Note 3j - See Note 1k - Extension Harness To Engine

NOTE: 1 BROWN/WHITE wire is taped back at instrument end. If installing on boat that isequipped with MerCruiser sterndrive, BROWN/WHITE wire is connected to the trim senderterminal block. Also can be used for an accessory (limit 5 amps).

NOTE: 2 An accessory fuse panel may be connected at this location. The combined currentdraw of the primary station and secondary station MUST NOT exceed 5 amps.

NOTE: 3 Tape back and insulate with at least four layers of electrical tape.

NOTE: 4 Connect wires together with screw and hex nut. Tighten securely and coat with Liq-uid Neoprene to help control corrosion; when dry, slide neoprene sleeve over connection.


Page 4E-12 90-861329--1 MARCH 1999

Battery Meter Gauge

72814

a

b

c

a - Lamp Mounting Holeb - PURPLE (or WHITE) Jumper Wire From This Terminal To “i” (Or +) Terminal On

Water Temperature Or Oil Pressure Gaugec - BLACK Jumper Wire From This Terminal To Ground (–) Terminal On Water

Temperature Or Oil Pressure Gauge

Cruiselog

72815

a

b

a - Connect to Ignition Switch Activated 12 Volt Positive (+) Source (PURPLE Wire)b - Connect to Negative (–) Ground (BLACK Wire)


90-861329--1 MARCH 1999 Page 4E-13

Fuel Gauge and Sender

72816

ab

c

d

e

f

PNK

PUR

BLK

BLK

BLK

BLK BLK

PNK

PNK

Either Guage Uses Either Sendera - Fuel Guage (Black Case)b - See Note 1c - Tank Senderd - See Note 2e - Fuel Tankf - Sender Capsule

NOTE: 1 Connect to “I” (Ignition) Terminal Or Accessory Terminal Of Ignition Switch

NOTE: 2 Connect to NEGATIVE (–) Battery Terminal Or Suitable Ground (–).


Page 4E-14 90-861329--1 MARCH 1999

Audio Warning System

WARNINGBuzzer is not external ignition-proof; therefore, DO NOT mount buzzer in engine orfuel tank compartments.

74046

Water Temperature Gauge

72819

ab

c

a - BLACK (a) Ground (–)b - PURPLE Switched 12 (+)_Volt Terminalc - TAN Sender Lead


90-861329--1 MARCH 1999 Page 4E-15

Oil Pressure Gauge

72819

b

c

a

a - BLACK Ground (–)b - PURPLE Switched 12 Volt (+) Terminalc - LIGHT BLUE Sender Lead

Clock

72818

a

b

ca

a - Connect To A Terminal On An Adjacent Gauge Or To Another Suitable Ground(–)

b - Connect to Instrument Harness RED/PURPLE Lead And Slide A RubberSleeve Over Connection

c - Connect To An “I” Terminal Of An Adjacent Gauge Or To Any Switched 12 (+)Volt Terminal


Page 4E-16 90-861329--1 MARCH 1999


5A

FUEL PUMPSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 5A-1

FUEL SYSTEMSection 5A - Fuel Pump

Table of Contents

Identification 5A-2. . . . . . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 5A-2. . . . . . . . . . . . Torque Specifications 5A-3. . . . . . . . . . . . . . . . . . Tools 5A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants 5A-3. . . . . . . . . . . . . . . . . . . Specifications 5A-3. . . . . . . . . . . . . . . . . . . . . . . . . Precautions 5A-4. . . . . . . . . . . . . . . . . . . . . . . . . . Fuel Delivery System 5A-5. . . . . . . . . . . . . . . . . .

Recommendations 5A-5. . . . . . . . . . . . . . . . . . Description 5A-5. . . . . . . . . . . . . . . . . . . . . . . .

Fuel System Components 5A-6. . . . . . . . . . . . . . Water Separating Fuel Filter 5A-6. . . . . . . . . . . .

Replacement 5A-7. . . . . . . . . . . . . . . . . . . . . . . Water Separating Fuel Filter 5A-8. . . . . . . . . . . .

Replacement 5A-8. . . . . . . . . . . . . . . . . . . . . . . Testing Fuel Pump 5A-9. . . . . . . . . . . . . . . . . . . . Fuel Pump Replacement 5A-10. . . . . . . . . . . . . .

Removal 5A-10. . . . . . . . . . . . . . . . . . . . . . . . .

FUEL PUMP SERVICE MANUAL NUMBER 26

Page 5A-2 90-861329--1 MARCH 1999

NOTICE

For information and procedures on “Troubleshooting,” refer to SECTION 1C.

Identification

Carter Fuel Pump




WARNINGAvoid gasoline fire or explosion. Improper installation of brass fittings or plugs intofuel filter base can crack casting and/or cause a fuel leak.

• Apply #592 Loctite Pipe Sealant with Teflon to threads of brass fitting or plug.DO NOT USE TEFLON TAPE.

• Thread brass fitting or plug into fuel filter base until finger tight.

• Tighten fitting or plug an additional 1-3/4 to 2-1/4 turns using a wrench. DO NOTOVERTIGHTEN.

• Install fuel line. To prevent overtightening, hold brass fitting with suitablewrench and tighten fuel line connectors securely.

• Check for fuel leaks.


90-861329--1 MARCH 1999 Page 5A-3


Description lb-ft Nm

Fuel Inlet and OutletFittings

Tighten finger tight then 1-3/4 to 2-1/4 additional turnswith wrench. (See Note)

Fuel Line to Fuel OutletFitting

Securely

Fuel Pump to Block 20 27

NOTE: Apply #592 Loctite Pipe Sealant with Teflon. Do not use Teflon Tape.

Tools


Fuel Pressure Gauge 91-16850A2

Lubricants/Sealants



Quicksilver Needle Bearing Grease 92-825265A1

Loctite Pipe Sealant with TEFLON Obtain Locally

Specifications

Type of Fuel Pump Carter

Pump Pressure (1800 rpm) 5-1/4 - 6-1/4 PSI (36-44 kPa)


Page 5A-4 90-861329--1 MARCH 1999

Precautions


WARNINGBe careful when changing fuel system components; gasoline is extremelyflammable and highly explosive under certain conditions. Be sure that ignition keyis OFF. DO NOT smoke or allow sources of spark or flame in the area whilechanging fuel filters. Wipe up any spilled fuel immediately.

WARNINGMake sure that no fuel leaks exist before closing engine hatch.

CAUTIONDO NOT operate engine without cooling water being supplied to seawater pickuppump, or pump impeller will be damaged and subsequent overheating damage mayresult.








90-861329--1 MARCH 1999 Page 5A-5

Fuel Delivery SystemRecommendations

WARNINGBoating industry standards (BIA, ABYC, etc.) federal standards and Coast Guardregulations MUST BE adhered to when installing fuel delivery system.

When designing and installing fuel delivery system, the following information MUST BEobserved:

1. Fuel tank should be mounted below carburetor level, if possible. If tank is mountedabove carburetor level, gravity feed may cause carburetor fuel inlet needle to unseat,and flooding may result.

2. Fuel pickup should be at least 1 in. (25 mm) from the bottom of the fuel tank to preventpicking up water or other impurities.

3. Fuel lines used MUST BE Coast Guard approved (USCG type A) and MUST NOT BESMALLER THAN 3/8 in. (9.5 mm) I.D. On installations where long lines or numerousfittings are required, larger size lines should be used.

4. Fuel line should be installed free of stress and firmly secured to prevent vibration and/orchafing.

5. Sharp bends in fuel line should be avoided.

6. A flexible fuel line must be used to connect fuel line to engine to absorb deflection whenengine is running.

DescriptionThe fuel system consists of fuel tank(s), a water separating fuel filter, an electric fuel pumpand a carburetor.

The fuel is stored in the fuel tank. When the fuel pump is energized by turning on ignitionswitch, fuel is drawn from the fuel tank, through the water separating filter, by the electricfuel pump.

The fuel is pushed through the fuel line to the carburetor where it is metered and suppliedto the engine.


Page 5A-6 90-861329--1 MARCH 1999

Fuel System Components

FUEL SYSTEM

50830

a

b

c de

f

g

h

i

Typicala - Fuel Tankb - Anti Siphon Valvec - Water Separating Fuel Filter, if equippedd - Fuel Pumpe - Carburetorf - Fuel Filterg - Vent Hoseh - Fuel Linei - Sight Tube

Water Separating Fuel Filter

The fuel filter, if equipped, consists of the fuel filter base and filter element.

72678

a

c

b

a - Filter Mounting Bracketb - Filter Elementc - Sealing Ring

Filter should be replaced when fuel flow is restricted or filter flow is questionable. DO NOTattempt to flush out filter.


90-861329--1 MARCH 1999 Page 5A-7

Replacement

NOTICE

Refer to “Precautions,” in this section, BEFORE proceeding.


2. Remove fuel filter from base. A filter wrench may be needed to loosen element.

3. Lubricate sealing ring(s) of new filter with SAE engine oil.

4. Install new filter, tightening securely by hand.

5. Reconnect battery cables. Make sure water is supplied to cooling system and startengine. Check for fuel leaks.

72678

a

c

b

a - Filter Base/Mounting Bracketb - Filter Elementc - Sealing Ring


Page 5A-8 90-861329--1 MARCH 1999

Water Separating Fuel Filter

NOTICE


Replacement

INSPECTION

Fuel pumps are equipped with a sight tube. Any evidence of fuel in the sight tube indicatesa ruptured diaphragm and fuel pump must be replaced immediately.

50738

a

b

a - Sight Tubeb - Fuel Fitting

NOTE: This fuel pump must be replaced as an assembly; it is not repairable with adiaphragm kit.


CAUTIONPlug fuel supply hose after removal to prevent fuel from leaking into boat.

2. Remove safety wire.

3. Loosen screw from filter bowl bail and release bail from fuel pump housing.

4. Remove bowl, filter element, spring, and gasket from fuel pump.

5. Install new filter.

6. Tighten retaining screw securely.

7. Install safety wire and tighten securely.

8. Start and run engine.

9. Check for gasoline leaks.

10. If leaks exist, STOP ENGINE and recheck connections.


90-861329--1 MARCH 1999 Page 5A-9

Testing Fuel Pump

NOTICE



2. Remove fuel line from carburetor or outlet side of fuel pump.

3. Install Fuel Pressure Connector (91-18078) to carburetor or fuel pump and reinstall fuelline. Tighten connector and fuel line securely.

4. Connect fuel pressure test gauge to connector.

75310

71561

a

b

c

a - Fits into Carburetorb - Fuel Line Connectionc - Fuel Gauge Barb

5. Reconnect battery cables, start engine, and run at idle, making sure water is suppliedto the cooling system.

6. Fuel pressure should be within specifications. If not, replace fuel pump.

7. Remove fuel pressure gauge and connector tool. Reconnect fuel line to fuel pump.


Page 5A-10 90-861329--1 MARCH 1999

Fuel Pump ReplacementRemoval

1. Remove fuel inlet and outlet lines at fuel pump.

2. Remove sight tube.

50738

a

b

a - Sight Tubeb - Fuel Fitting

3. Remove 2 fuel pump mounting bolts and lock-washers, pump and gasket.

CAUTIONPlug fuel lines after disconnecting from fuel pump to eliminate any chance of fuelsiphoning into bilge.

4. Coat both sides of new gasket with Perfect Seal.

5. Install new gasket on fuel pump.

6. Install pump.

7. Coat mounting bolts with Perfect Seal.

8. Torque mounting bolts to specifications.







9. Install fuel outlet fitting (from old pump) into fuel pump.

10. Install fuel line to fuel outlet fitting. Tighten securely.

11. Install fuel inlet fitting to fuel pump.

12. Install sight tube and fuel supply line.

13. Start engine and check for fuel leaks.


90-861329--1 MARCH 1999 Page 5A-11



Page 5A-12 90-861329--1 MARCH 1999


5B

MERCARB 2 BARREL CARBURETORSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 5B-1

FUEL SYSTEMSection 5B - MERCARB 2 BARREL CARBURETOR

Table of Contents

Identification 5B-2. . . . . . . . . . . . . . . . . . . . . . . . . . Replacement Parts Warning 5B-3. . . . . . . . . . . . Torque Specifications 5B-3. . . . . . . . . . . . . . . . . . Tools 5B-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Special Tools 5B-3. . . . . . . . . . . . . . . . . . . . . . . Specifications 5B-4. . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Adjustment Specifications 5B-4. High Altitude Re-Jetting 5B-5. . . . . . . . . . . . .

Important Service Information 5B-5. . . . . . . . . . . Flooding at Idle RPM 5B-5. . . . . . . . . . . . . . . . Needle/Seat Change 5B-6. . . . . . . . . . . . . . . . Adjustable Accelerator Pump Lever 5B-6. . .

Description 5B-7. . . . . . . . . . . . . . . . . . . . . . . . . . . Precautions 5B-7. . . . . . . . . . . . . . . . . . . . . . . . . .

Fuel Supply Connections 5B-7. . . . . . . . . . . .

Maintenance 5B-8. . . . . . . . . . . . . . . . . . . . . . . . . . Flame Arrestor with Carburetor Cover 5B-8. Fuel Inlet Filter 5B-9. . . . . . . . . . . . . . . . . . . . . Choke Inspection 5B-10. . . . . . . . . . . . . . . . . .

Adjustments 5B-10. . . . . . . . . . . . . . . . . . . . . . . . . Pump Rod 5B-10. . . . . . . . . . . . . . . . . . . . . . . . Choke Setting 5B-12. . . . . . . . . . . . . . . . . . . . . Preliminary Idle Speed and Mixture 5B-12. . Final Idle Speed and Mixture 5B-13. . . . . . . .

Repair 5B-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 5B-15. . . . . . . . . . . . . . . . . . . . . . . . . Installation 5B-15. . . . . . . . . . . . . . . . . . . . . . . . Exploded View Parts List 5B-17. . . . . . . . . . . Disassembly 5B-18. . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 5B-25. . . . . . . . . . . . Reassembly 5B-26. . . . . . . . . . . . . . . . . . . . . .

MERCARB 2 BARREL CARBURETOR SERVICE MANUAL NUMBER 26

Page 5B-2 90-861329--1 MARCH 1999

Identification

72680

330495652301

ab

Carburetor Part Number Locationa - Part Numberb - Date Code

Data Code Explanation: Example 2301

First Figure is Year:2 = 1992, 3 = 1993, etc.Second Figure is Month:2 = February, 3 = March, etc.X = October, Y = November, Z = DecemberThird and Fourth Figures are Day of Month:01 = First day, 02 = Second day, etc.

72779

a

b

Venturi Cluster Identificationa - Identification Number (See Specifications)b - Accelerator Pump Discharge Holes


90-861329--1 MARCH 1999 Page 5B-3






Carburetor To Manifold 20 27

Fuel Line to Carburetor 18 24

Fuel Inlet Filter Nut 18 24

Tools


Tachometer 79-17391A1

Universal Carburetor Gauge 91-36392

Special Tools

Boroughs Special Tools


Boroughs Special Tool and Equipment Inc.2429 N. Burdick StreetKalamazoo,MI 49007

(616) 345-5163

Float Gram Scale BT 8128 B


Page 5B-4 90-861329--1 MARCH 1999

Specifications

NOTICE

Unit Of Measurement: U.S. Quarts (Liters)All capacities are approximate fluid measures.

Carburetor Adjustment Specifications

Engine Model 3.0L

Carburetor Type MerCarb 43 mm MerCarb 36 mm

Carburetor Number 3310-807504 1389-807505

Float Level 3/8 (10)

Spring Loaded Needle 9/16 (14) (See Note)

Float Drop 1-3/32 (27) (See Note)

Pump Rod 1-5/32 (29)

Choke Setting Two Marks To The Lean Side

Choke Unloader 5/64 [080] (2)

Idle Mixture Screws 1-1/4 Turns Factory Setting

Float Weight 9 Grams Maximum

Primary Jet Size 1.55 mm 1.45 mm

Power Valve Size 4 x 0.65 mm 2 x 0.60 mm

Venturi Cluster I.D. Number 171 470

Accelerator PumpDischarge Hole Size

.025 (0.635) .035 (0.89)

All measurements are + 1/64 in. (0.4 mm).

NOTE: Float drop measured from air horn (with gasket in place) to toe of float.


90-861329--1 MARCH 1999 Page 5B-5

High Altitude Re-JettingEngine flooding problems, at idle rpm, are generally related to the altitude (above sea level)at which they are operated. If engine is running too rich at higher elevation, order a smallerjet from the chart. A jet stamped “165” is a 1.65 mm jet.

Model CarburetorPart Number

5000 ft(1525 m)

and Below

5000-9000 ft(1525-2745 m)

9000 ft(2745 m)

and Above3.0L 3310-807504 1.55 mm 1.55 mm 1.45 mm

JET SIZES

Jet Size Quicksilver Part Number

1.30 3302-811849

1.35 3302-811850

1.40 3302-811851

1.45 3302-9050

1.50 3302-811852

1.55 3302-811853

1.60 3302810923

1.65 3302-9058

1.70 3302-9055

1.75 3302-881854

1.80 3302-811855

1.85 3302-811856

1.90 3302-811857

Important Service Information

Flooding at Idle RPMIf your engine floods at idle rpm, check the following:

1. Problem in ignition system causing engine to run rough.

2. Idle mixture screw adjusted incorrectly.

3. Bad needle and seat.

4. Incorrect float level drop.


Page 5B-6 90-861329--1 MARCH 1999

Needle/Seat ChangeIf the preceding steps failed to correct the problem, change the needle/seat to the other type.MerCarbs are equipped with either the solid or the spring loaded needle.

72290

a

b

Needle and Seat Assembliesa - Spring Loaded Type Needle (Kit 3302-9029)b - Solid Type Needle (Kit 3302-9407)

Adjustable Accelerator Pump LeverThis new 3-holed lever will allow you to change the amount of fuel delivered to the engineby the accelerator pump. The hole closest to the lever’s shaft will give the same amount offuel as the single hole lever did. The center hole gives approximately 0.5 cc less fuel andthe hole farthest away will give about 1.0 cc less fuel.

73131

a

cb

a - Full Accelerator Pump Strokeb - 0.5 cc Less Fuel per Strokec - 1.0 cc Less Fuel per Stroke

The technician should be able to correct most “bogging” problems with this 3-holed lever,providing the “bogging” is caused by the carburetor. When installing the 3-holed lever,remove any metal ball that someone may have put in the accelerator pump well to limit pumptravel. Also, make sure that the duration spring on the accelerator pump is stock and hasn’thad several coils cut off. Make sure the venturi cluster is the correct one as outlinedpreviously under “Specifications.”


90-861329--1 MARCH 1999 Page 5B-7

Description

This MerCarb carburetor is a two bore carburetor and has a separate fuel feed for eachventuri. This model also is equipped with an electric choke. A removable venturi cluster(secured to float bowl assembly) has the calibrated main well tubes and pump jets built intoit. The venturi cluster is serviced as a unit. The serviceable main metering jets are bleedsto properly meter the correct fuel/air mixture to the engine.

Precautions


WARNINGBe careful when cleaning flame arrestor and crankcase ventilation hose; gasolineis extremely flammable and highly explosive under certain conditions. Be sure thatignition key is OFF. DO NOT smoke or allow sources of spark or open flame in areawhen cleaning flame arrestor and crankcase ventilation hose.

WARNINGBe careful when changing fuel system components; gasoline is extremely flam-mable and highly explosive under certain conditions. Be sure that ignition key isOFF. DO NOT smoke or allow sources of spark or flame in the area while changingfuel filter. Wipe up any spilled fuel immediately.

WARNINGMake sure no fuel leaks exist, before closing engine hatch.

Fuel Supply Connections

CAUTIONDO NOT operate engine without cooling water being supplied to water pickup holesin gear housing, or water pump impeller will be damaged and subsequent overheat-ing damage to engine may result.


Page 5B-8 90-861329--1 MARCH 1999

Maintenance

Flame Arrestor with Carburetor Cover

NOTICE

Refer to “Precautions” in this section, BEFORE proceeding.

1. Remove in the following order:

a. Nut.

b. Sealing washer.

c. Crankcase ventilation hoses from flame arrestor and rocker arm covers.

d. Flame arrestor.

2. Clean and inspect:

a. Clean flame arrestor in solvent and blow dry with compressed air.

b. Clean crankcase ventilation hoses.

c. Inspect crankcase ventilation hoses for cracks or deterioration, and replace if neces-sary.

3. Install in the following order:

a. Flame arrestor.

b. Crankcase ventilation hoses to flame arrestor and rocker arm covers.

c. Sealing washer.

d. Nut (tighten securely).

72086

ab

c

d

c

a - Nutb - Sealing Washerc - Crankcase Ventilation Hosed - Flame Arrestor


90-861329--1 MARCH 1999 Page 5B-9

Fuel Inlet Filter

NOTICE


1. Remove in the following order:

a. Fuel line from fuel inlet filter nut.

b. Fuel inlet filter nut and small gasket.

c. Large gasket.

d. Filter.

e. Spring.

f. Small gasket - from inside filter nut.

72406

b c d e

f

a

a - Fuel Lineb - Fuel Inlet Filter Nutc - Gasket (Large)d - Gasket (Small)e - Filterf - Spring

2. Clean filter nut and spring in solvent and dry with compressed air.

3. Install in the following order:

a. Spring - place in carburetor body.

b. Filter - open end to inlet filter nut.

c. Small gasket - place inside filter nut.

d. Large gasket - place over filter nut threads.

e. Fuel inlet filter nut - torque nut to 18 lb-ft (24 Nm).

f. Fuel line - torque to 18 lb-ft (24 Nm).


Page 5B-10 90-861329--1 MARCH 1999

Choke InspectionThe choke does not require any periodic maintenance; however, if a choke malfunction issuspected, the following should be done:

1. With engine turned OFF, remove flame arrestor.

2. Open and close choke several times, and check for binding, loose or disconnectedlinkages, or other signs of damage.

3. If choke or linkage binds, sticks, or works sluggishly, clean with carburetor chokecleaner. Follow directions on can.

IMPORTANT: Choke valve and shaft and lever assembly is not serviceable. If valveand/or shaft and lever assembly is worn or damaged, air horn assembly must bereplaced.

Adjustments

NOTICE


Pump Rod1. Loosen idle speed screw until it no longer contacts idle cam.

72284

b

a

a - Idle Speed Screwb - Idle Cam


90-861329--1 MARCH 1999 Page 5B-11

2. With throttle valves completely closed, measure from flame arrestor mounting surfaceto top of pump rod.

72682

a

a - See Specifications

3. Carefully bend pump rod (where shown) to obtain specified dimension.

72683

a

b

a - Pump Rodb - Bend Here


Page 5B-12 90-861329--1 MARCH 1999

Choke SettingNormal choke setting is such that scribed mark on cover is in line with long case mark onchoke housing.

72403

a

cb

a - Scribed Markb - More Chokec - Less Choke

If choke adjustment is necessary:

1. Loosen three choke cover retaining screws and adjust as shown.

2. Tighten three choke cover retaining screws securely.

Preliminary Idle Speed and MixtureIMPORTANT: The following adjustments will provide a sufficient idle speed and mix-ture for starting engine. Final adjustments must be made with engine running.

1. Back out idle speed screw until it no longer contacts idle cam. Turn idle speed screw inuntil it just contacts idle cam, then turn screw in an additional two turns.

72284

a

b

a - Idle Speed Screwb - Idle Cam

IMPORTANT: DO NOT turn idle mixture needle tightly against seat (in the followingstep), as damage to seat and/or needle may result.


90-861329--1 MARCH 1999 Page 5B-13

2. Turn idle mixture needle in until lightly seated, then back needle out 1-1/4 turns.

72281

a

a - Idle Mixture Needle

Final Idle Speed and Mixture

EMISSIONS CARBURETOR

Sealed Carburetor Mixture Screw

The carburetor on this engine has a seal on the carburetor mixture screw. This seal preventsadjustment of the fuel mixture setting.

CAUTIONDo not remove mixture screw seal and/or attempt to adjust fuel mixture setting.Tampering with the mixture setting on this engine could affect the exhaustemissions level, thus voiding the emissions certification. This seal should only beremoved by an authorized dealer or emissions testing agency.

NON-EMISSIONS CARBURETOR

IMPORTANT: Boat must be in the water and engine at normal operating temperatureto accurately check and adjust idle speed and mixture.

Carburetor should be set so that engine idles smoothly within range given under “Specifica-tions,” with boat in the water, engine at normal operating temperature and drive unit in for-ward gear. To adjust idle speed and mixture, proceed as follows:

IMPORTANT: DO NOT attempt to compensate for other engine problems (incorrectignition timing, faulty ignition components, low compression, vacuum leaks, etc.)with carburetor adjustments. This will only cover the problem, which must be cor-rected if engine is to achieve maximum fuel economy and performance.

1. Connect an accurate shop tachometer to engine.

IMPORTANT: DO NOT turn idle mixture needle tightly into seat, as damage to needleand/or seat may result.

72281

a

a - Idle Mixture Needle


Page 5B-14 90-861329--1 MARCH 1999

2. If new or rebuilt carburetor has been installed, turn idle mixture needle in (clockwise)until it lightly contacts seat, then back out needle 1-1/4 turns. This will provide a sufficientsetting to allow starting engine.

3. Start engine and run at 1500 rpm until engine reaches normal operating temperature.

WARNINGDO NOT leave the helm unattended while performing idle speed and mixture adjust-ments, following. BE CAREFUL NOT TO ACCIDENTALLY ACCELERATE ENGINEWHILE PERFORMING ADJUSTMENTS.

4. With boat in open water, place remote control in forward gear, idle position.

5. Disconnect throttle cable barrel from anchor stud. Be sure not to lose spacer on anchorstud.

6. Adjust idle speed adjustment screw to obtain 550-600 rpm, in neutral gear.

7. With engine running at specified rpm, adjust idle mixture needle as follows:

a. Turn idle mixture needle in (clockwise) until the engine speed begins to drop due tolean mixture.

b. Turn idle mixture screw out (counterclockwise) until the speed begins to drop dueto rich mixture.

c. Turn screw in to a point between these two extremes to obtain maximum enginesmoothness and rpm.

d. Readjust idle speed adjustment screw until engine idles at 650-700 rpm in forwardgear.

IMPORTANT: Refer to Section 2 “Removal and Installation” for throttle cable installa-tion and adjustment.


90-861329--1 MARCH 1999 Page 5B-15

Repair

NOTICE


RemovalIMPORTANT: Carburetor malfunctions are, in many cases, caused by the presenceof dirt, water or other foreign matter in carburetor. To aid in diagnosis, carefullyremove carburetor from engine without draining fuel from bowl. Contents of fuelbowl may then be inspected for contamination as carburetor is disassembled.

1. Remove ventilation hose from flame arrestor, then remove flame arrestor.

IMPORTANT: Place a clean cloth in bores of carburetor to prevent dirt and foreignmaterial from falling into bores.

2. Turn fuel supply off at fuel tank.

3. Disconnect throttle cable from carburetor.

4. Remove fuel line from fuel inlet nut, using wrench to stabilize fuel inlet nut.

5. Remove fuel pump sight tube from carburetor.

6. Disconnect electric choke.

7. Remove carburetor attaching nuts and washers and remove carburetor.

IMPORTANT: Place a clean cloth over intake manifold opening to prevent dirt or for-eign material from entering manifold.

8. Remove and discard gaskets.

Installation1. Thoroughly clean gasket surfaces.

2. Place new carburetor base gasket on intake manifold. Install carburetor and secure withnuts and washers. Torque to 132 lb-in. (15 Nm).

3. If fuel inlet filter nut was disturbed, remove; clean all threads with brush and carburetorcleaner or Quicksilver Leveler.

4. Connect fuel line to fuel inlet filter nut, and while stabilizing filter nut with wrench, tightenfuel line fitting securely.

5. Connect fuel pump sight tube to fitting on carburetor.

6. Connect electric choke wires to choke cover.

7. Install throttle cable as explained in SECTION 2.

8. Install flame arrestor and crankcase ventilation hose.

9. Reconnect battery cables to battery.

10. Ensure that water is supplied to cooling system. Start engine and check for gasolineleaks. If leaks exist, STOP ENGINE IMMEDIATELY and recheck connections.

11. Adjust idle speed and idle mixture, as outlined under “Adjustments” as previously out-lined.


Page 5B-16 90-861329--1 MARCH 1999

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90-861329--1 MARCH 1999 Page 5B-17

Exploded View Parts List

1 - Rod - Accelerator Pump2 - Accelerator Pump Shaft and Lever

Assembly3 - Washer (Outer)4 - Washer (Inner)5 - Screw6 - Washer7 - Screw8 - Spring9 - Filter

10 - Gasket11 - Gasket12 - Nut-Fuel Inlet13 - Choke-Rod14 - Gasket15 - Clip - Retainer16 - Washer17 - Pump Shaft and Lever Assembly18 - Accelerator Pump Assembly19 - Spring20 - Screw21 - Inlet Needle and Seat (Spring

Loaded - Optional)22 - Baffle Plate23 - Float24 - Float Bowl25 - Cam-Idle26 - Screw27 - Idle Mixture Adjusting Needle28 - Spring29 - Washer30 - Nut

31 - Clip-Pump Rod32 - Washer-Locking33 - Nut34 - Throttle Lever35 - Spring36 - Screw - Idle Speed Adjustment37 - Throttle Body38 - Screw39 - Washer40 - Gasket41 - Check Ball42 - Spring43 - Retainer44 - Screw45 - Lever Assembly46 - Screw47 - Choke/Housing48 - Gasket49 - Air Horn50 - Inlet Needle And Seat51 - Pin52 - Screw53 - Gasket54 - Screw55 - Screw56 - Flat Washer57 - Lock Washer58 - Gasket59 - Venturi Cluster60 - Power Valve Assembly61 - Gasket62 - Gasket


Page 5B-18 90-861329--1 MARCH 1999

DisassemblyThe following is a step-by-step procedure for completely overhauling carburetor removedfrom engine. In many cases, however, complete overhaul is not necessary and, in thesecases, only the steps required to repair the carburetor malfunction should be performed.Read the instructions carefully to prevent doing any unnecessary steps.

IMPORTANT: Before performing any service on carburetor, it is essential that carbu-retor be placed in a holding fixture to prevent possible damage to throttle valves.

CHOKE HOUSING ASSEMBLY

1. Remove choke cover.

72403

a

a - Choke Cover

2. Remove choke lever. Remove choke housing.

72401

a

b

a - Choke Leverb - Choke Housing


90-861329--1 MARCH 1999 Page 5B-19

AIR HORN ASSEMBLY

1. Remove fuel inlet filter nut, washers, spring, and filter, as outlined previously.

2. Remove accelerator pump rod retaining clip. Pivot rod (as required) until retaining earon rod and slot in pump shaft and lever assembly align, allowing rod to be pulled out.

72283b

a

c

a - Accelerator Pump Rodb - Retainer Clipc - Pump Shaft and Lever Assembly

3. Remove idle cam screw. Also, remove choke rod by pivoting rod (as required) untilretaining ear on rod and slot in choke lever align, allowing rod to be pulled out.

72282

c

ab

a - Idle Cam Screwb - Idle Camc - Choke Rod


Page 5B-20 90-861329--1 MARCH 1999

4. Remove air horn attaching screws as shown.

72280

a

a

a

a

a - Air Horn Attaching Screws

5. Carefully lift air horn from float bowl assembly.

72400

a

b

a - Air Horn Assemblyb - Float Bowl Assembly

6. Invert air horn and carefully lay on bench.

7. Remove float hinge pin and lift float assembly from air horn.

72288

b

a

a - Float Hinge Pinb - Float Assembly


90-861329--1 MARCH 1999 Page 5B-21

8. Check float weight as shown.

72122

b

a

a - Grams Scaleb - Float

9. Remove air horn gasket and baffle.

72399b a

a - Baffleb - Air Horn Gasket

10. Remove needle assembly.

72287

a

b

a - Needle Assemblyb - Needle Seat


Page 5B-22 90-861329--1 MARCH 1999

11. Remove needle seat.

72289

c

ba

a - Needle Seatb - Gasketc - Screwdriver

72290

a

b

Needle and Seat Assembliesa - Spring Loaded Type Needle (Kit 3302-9029)b - Solid Type Needle (Kit 3302-9407)

12. Loosen accelerator pump screw. Slide pump shaft and lever assembly (and washer) outof air horn, then remove accelerator pump assembly.

72398

a

c

b

a - Setscrewb - Lever Assemblyc - Pump Assembly


90-861329--1 MARCH 1999 Page 5B-23

13. Remove retainer clip and washer from pump shaft and lever assembly, then removeaccelerator pump assembly.

72409

a

b

c

a - Pump Assemblyb - Retainer Clipc - Lever Assembly

FLOAT BOWL ASSEMBLY

1. Remove accelerator pump return spring from pump well.

72402

a

a - Accelerator Pump Spring

2. Remove power valve assembly and gasket.

72404

ba

a - Power Valve Assemblyb - Gasket (Not Shown)


Page 5B-24 90-861329--1 MARCH 1999

3. Remove main metering jets.

72291

bb

a

a - Main Metering Jetsb - Gaskets (Not Shown)

IMPORTANT: Use care when removing venturi cluster to prevent damaging brasstubes which protrude from bottom of cluster. DO NOT REMOVE TUBES. These tubesare permanently pressed into the venturi cluster and are not replaceable.

4. Remove three venturi cluster screws, and carefully lift cluster and venturi gasket straightup.

72292

a

b

a - Venturi Cluster Brass Tubesb - Gasket

5. Using needle-nose pliers, remove accelerator pump check ball spring retainer. Turnfloat bowl over to remove spring and check ball.

72407

a

b

a - Spring Retainerb - Spring and Check Ball (Not Shown)


90-861329--1 MARCH 1999 Page 5B-25

Cleaning and InspectionIMPORTANT: DO NOT use a wire or drill to clean jet passages or tubes in carburetor,as this may enlarge orifices and seriously affect carburetor calibration.

CAUTIONTo avoid damage to carburetor DO NOT leave carburetor in immersion type carbure-tor cleaner for more than two hours.

IMPORTANT: DO NOT clean float bowl gasket surfaces with a gasket scraper or knife,as sealing bead will be damaged and float bowl replacement will be necessary.

CAUTIONThe float assembly, float needle, accelerator pump plunger, and fuel filter MUSTNOT BE immersed in carburetor cleaner, as they will swell, harden, and/or distort.

72410

a

b

cd

a - Accelerator Pump Plungerb - Float Needlec - Fuel Filterd - Float Assembly

WARNINGAvoid personal injury by always wearing safety goggles when using compressedair.

1. Thoroughly clean all metal parts in a commercial carburetor cleaner, until all depositshave been removed. Follow cleaner manufacturer’s instructions for proper cleaning andrinsing procedure. Dry parts with compressed air.

2. Using compressed air, blow out all passages in carburetor to remove any foreignmaterial.

3. Wipe off all parts that cannot be cleaned in carburetor cleaner with a clean, dry cloth.

4. Carefully inspect all carburetor parts for wear and damage; pay particular attention tothe following:

a. Float Needle and Seat: If float needle or seat is worn or damaged, replace with newneedle and seat assembly.

IMPORTANT: Float needle and seat are factory matched and tested and should bereplaced as a set only.

b. Float Assembly and Hinge Pin: Check float density (to see if it is saturated withfuel) by comparing weight of float with specifications. If weight is high, float assemblymust be replaced. Check hinge pin and holes for wear.


Page 5B-26 90-861329--1 MARCH 1999

c. Fuel and Air Passages: Passages must be perfectly clean for proper carburetoroperation.

d. Accelerator Pump Plunger and Return Spring: Inspect pump plunger cup, pumpplunger spring (on pump assembly) and return spring.

e. Power Piston Spring: Check power piston spring for weakness or distortion.

f. Idle Mixture Needle: Inspect idle mixture needle. If damaged, needle must bereplaced.

g. Levers and Linkages: Check levers, links and rods for wear.

h. Throttle Valve and Shaft: Check throttle shaft for excessive looseness in throttlebody. Check throttle valve and shaft for binding through entire operating range,making sure valve opens and closes completely. Throttle body assembly must bereplaced if throttle valve and shaft are worn or damaged.

i. Choke Valve and Shaft and Lever Assembly: Check shaft and lever assembly forexcessive looseness in air horn assembly. Check choke valve and shaft and leverassembly for binding through entire operating range, making sure valve opens andcloses completely. Air horn assembly must be replaced if choke valve and shaft andlever assembly are worn or damaged.

j. Inspect Casting for visible damage. Inspect gasket surfaces. Inspect acceleratorpump plunger well for scoring or deposits.

ReassemblyIMPORTANT: DO NOT force idle mixture needle against seat as damage to needleand/or seat will result.

FLOAT BOWL ASSEMBLY

IMPORTANT: Place float bowl and throttle assemblies in holding fixture to preventthrottle valves from being damaged.

1. Install check ball, spring, and retainer in passage as shown. Push retainer firmly intoslots.

72408

ab

c

a - Check Ballb - Springc - Retainer


90-861329--1 MARCH 1999 Page 5B-27

2. Install new gasket on venturi cluster as shown.

72296

a

b

a - Venturi Cluster (I.D. No. 421)b - Gasket

3. Install venturi cluster in carburetor as shown.

72397

a

b

a - Venturi Clusterb - Gasket

4. Install flat washer and new fiber washer on center screw. Lockwashers and flat washersare used on outer screws. Tighten screws evenly and securely.

72405

ab

c

b

a - Center Screwb - Outside Screwsc - Fiber Washer


Page 5B-28 90-861329--1 MARCH 1999

5. Install main metering jets with gaskets as shown. Tighten securely.

72291

a

bb

a - Main Metering Jetsb - Gaskets (Not Shown)

6. Install power valve with new gasket. Tighten securely.

72404

ab

a - Power Valveb - Gasket (Not Shown)

7. Place accelerator pump spring in pump well.

72402

a

a - Accelerator Pump Spring


90-861329--1 MARCH 1999 Page 5B-29

AIR HORN ASSEMBLY

IMPORTANT: Accelerator pump assembly MUST BE installed correctly. If pumpassembly is installed incorrectly, top of pump assembly will contact air horn casting.

1. If accelerator pump assembly was removed from pump lever, secure pump assemblyto pump lever with washer and retainer clip, as shown.

72409

ab

c

a - Pump Assemblyb - Retainer Clipc - Pump Lever

2. Insert pump shaft and lever assembly (and washer) into air horn; then, align indexedhole in pump lever with shaft and lever assembly and slide shaft all the way into leverso that shoulder on shaft is hitting lever. Tighten setscrew securely.

72398

a

b

c

a - Setscrewb - Lever Assemblyc - Pump Assembly


Page 5B-30 90-861329--1 MARCH 1999

3. Install needle seat and gasket. Tighten securely.

72289

ab

c

a - Needle Seatb - Gasketc - Screwdriver

IMPORTANT: Float needle and needle seat are factory matched and tested andshould be replaced as a set only.

4. Place needle assembly in needle seat.

72287

a

b

a - Needle Assemblyb - Needle Seat

5. Install baffle and gasket.

72399

ab

a - Baffleb - Gasket


90-861329--1 MARCH 1999 Page 5B-31

6. Install float assembly and hinge pin. Pivot float assembly up and down on hinge pin toensure it moves freely.

72297

b

a

a - Float Assemblyb - Float Hinge Pin

FLOAT LEVEL

1. Turn air horn upside down. Pivot float assembly up and down on hinge pin to ensure itmoves freely.

IMPORTANT: Before checking float level, raise float and allow it to fall; however, DONOT force downward by hand.

2. Measure float level using Universal Carburetor Gauge (91-36392). Measure from gas-ket to toe of float.

72298a

a - Measure from This Point to Gasket

72687

a

a - Measurement With 2 Piece Solid Inlet Needle - 3/8 in. (10 mm)b - Measurement With Spring Loaded Inlet Needle - 9/16 in. (14 mm)


Page 5B-32 90-861329--1 MARCH 1999

3. Bend float arm up or down at point shown to obtain specified dimension.

72688

a

a - Bend Float Arm at This Point

4. Visually check float alignment after adjustment.

FLOAT DROP

1. Hold air horn right side up to allow float to hang free.

2. Measure float drop using Universal Carburetor Gauge (91-36392). Measure from gas-ket to toe of float.

72689

a

a - Measurement - 1-3/32 in. (27 mm)

3. Bend float assembly tang, as shown, to obtain specified dimension.

72690

a

a - Float Assembly Tang


90-861329--1 MARCH 1999 Page 5B-33

4. Recheck BOTH float level and float drop.

5. Carefully place air horn on float bowl, making sure accelerator pump is correctly posi-tioned in fuel well. Lower air horn straight down to install.

72400

a

b

a - Air Horn Assemblyb - Float Bowl Assembly

6. Install seven short and one long air horn attaching screws. Tighten screws evenly andsecurely.

72280

a

a

a

aa - Air Horn Attaching Screws

7. Place end of choke rod in choke lever and collar assembly.

72299

a

b

a - Choke Rodb - Choke Lever and Collar Assembly


Page 5B-34 90-861329--1 MARCH 1999

8. Place idle cam on choke rod.

72392

ab

a - Idle Camb - Choke Rod

9. Secure idle cam (with choke rod installed on cam) on float bowl assembly, using screw.Check that cam is free to move without binding.

72282

c

a

b

a - Screwb - Idle Camc - Choke Rod

10. Place accelerator pump rod (end with ear) in hole in pump shaft and lever assembly.

72393

a

b

a - Accelerator Pump Rodb - Pump Shaft and Lever Assembly


90-861329--1 MARCH 1999 Page 5B-35

11. Insert remaining end of accelerator pump rod into hole in throttle lever and secure withretainer clip.

72283ac b

a - Accelerator Pump Rodb - Throttle Leverc - Retainer Clip

CHOKE HOUSING ASSEMBLY

1. Install choke housing on air horn; tighten screws securely. Install choke lever; tightenscrew securely.

72401

a

b

c

a - Choke Housingb - Choke Housing Attaching Screwsc - Choke Lever

2. Install choke cover. Make sure hook on end of choke coil engages with choke lever.Rotate choke cover until index marks align as shown. Tighten screws securely.

72403

ac b

a - Scribed Markb - More Chokec - Less Choke


Page 5B-36 90-861329--1 MARCH 1999


6A

SEAWATER COOLED MODELSSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 6A-1

COOLING SYSTEMSection 6A - Seawater Cooled Models

Table of Contents

Torque Specifications 6A-2. . . . . . . . . . . . . . . . . . Tools 6A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 6A-2. . . . . . . . . . Specifications 6A-2. . . . . . . . . . . . . . . . . . . . . . . . . Identification 6A-3. . . . . . . . . . . . . . . . . . . . . . . . . . Flushing Cooling System 6A-3. . . . . . . . . . . . . . .

Sterndrive Seawater Pickup Pump 6A-4. . . . Thermostat 6A-5. . . . . . . . . . . . . . . . . . . . . . . . . . .

Removal 6A-5. . . . . . . . . . . . . . . . . . . . . . . . . .

Testing 6A-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation 6A-7. . . . . . . . . . . . . . . . . . . . . . . . . . . Cold Weather Or Extended Storage 6A-7. . . . .

Precautions 6A-7. . . . . . . . . . . . . . . . . . . . . . . . Draining Instructions 6A-8. . . . . . . . . . . . . . . . Recommissioning 6A-12. . . . . . . . . . . . . . . . . .

Auxiliary Hot Water Heater Installation 6A-14. . Cooling System Flow Diagram 6A-16. . . . . . . . .

SEAWATER COOLED MODELS SERVICE MANUAL NUMBER 26

Page 6A-2 90-861329--1 MARCH 1999

NOTICE

For information and procedures on “Troubleshooting,” refer to SECTION 1C.

NOTICE

For “Cold Weather Or Extended Storage” information and procedures, refer toSECTION 1B.



Power Steering Pump Bracket 30 41

Thermostat Cover 30 41

Thermostat Housing 30 41

Drain Plugs1

Hose ClampsTighten Securely

1 Coat threads with Quicksilver Perfect Seal before installing except blue plastic plugs with rubber seals.

Tools


Flush Device 44357A2




Specifications

Cooling System Capacity 9 (8.5)

Thermostat (Brass) 143°F (62°C)

Thermostat (Stainless) 160°F (71°C)


90-861329--1 MARCH 1999 Page 6A-3

Identification

7180172674a

b

Brass Thermostat1 Stainless Steel Thermostat2

1Serial number break:0L340999 and below.2Serial number break:0L341000 and above.

Flushing Cooling System

If engine is operated in salty, polluted or mineral laden waters, cooling system should beflushed periodically (preferably after each use) to reduce corrosion and prevent theaccumulation of deposits in the system. Cooling system also should be thoroughly flushedprior to storage.

WARNINGWhen flushing cooling system with boat out of water, be certain that area in vicinityof propeller is clear and no one is standing nearby.

CAUTIONIf boat is in the water, seacock (if equipped) must be left closed until engine is tobe restarted to prevent water from flowing back into cooling system. If boat is notfitted with a seacock, water inlet hose must be left disconnected and plugged, toprevent water from flowing into cooling system and/or boat. As a precautionarymeasure, attach a tag to the ignition switch or steering wheel with the warning thatthe seacock must be opened or the water inlet hose reconnected prior to startingthe engine.

CAUTIONObserve temperature gauge on dash to ensure that engine does not overheat.



Page 6A-4 90-861329--1 MARCH 1999

Sterndrive Seawater Pickup Pump

72672

a

b

a - Flush Deviceb - Water Hose

1. Install flush device and connect water hose between it and water tap.

2. Saltwater areas and boat in the water:

a. Raise sterndrive unit to full trailer position.

b. Install flush device over water intake holes.

c. Lower sterndrive unit to full down position.

3. Partially open water tap (approximately 1/2 maximum capacity) and allow coolingsystem to fill completely. DO NOT use full water tap pressure.


4. Place remote control in NEUTRAL, idle speed position and start engine. Operate engineat idle speed, in NEUTRAL, for about 10 minutes, or until discharge water is clear. Watchtemperature gauge on instrument panel to ensure that engine does not overheat.

5. Stop engine, turn off water tap and remove flush device.


90-861329--1 MARCH 1999 Page 6A-5

Thermostat

Removal1. Drain water from cylinder block and exhaust manifold.

2. Disconnect hoses from thermostat cover.

3. Remove thermostat cover attaching bolts and lockwashers.

4. Remove thermostat from thermostat housing or cover.

73572

ab

140° Thermostat Housing Showna - Thermostat Coverb - Attaching Bolts

Testing

1. Clean thermostat in soap and water to remove any deposits or debris.

2. Inspect for corrosion or other visible damage.

3. If thermostat is suspected of producing insufficient engine temperature, checkthermostat for leakage by holding it up to a lighted background. Light leakage aroundthe thermostat valve indicates that thermostat is not closing completely and should bereplaced. (A small amount of leakage one or two locations around the valve perimeteris acceptable.)

4. Check opening and closing temperature of the thermostat (using a tester similar to oneshown below), as follows:

a. Fill tester to within 1 inch (25 mm) of top with tap water. DO NOT use distilled water.

b. Open thermostat valve and insert nylon string. Position thermostat on string so thatit will be just below water level when suspended, then allow valve to close. Suspendthermostat in water.


Page 6A-6 90-861329--1 MARCH 1999

c. Place thermometer in container and position so that bottom of thermometer is evenwith bottom of thermostat. DO NOT allow thermometer to touch container.

72675

a

b

c

a - Thermometerb - Nylon Stringc - Thermostat

IMPORTANT: When performing Steps d through f, water must be thoroughly agitatedto obtain accurate results.

d. Plug in tester and observe temperature at which thermostat opens (thermostatdrops off thread). Thermostat must open at specified temperature stamped onthermostat.

e. Continue heat water until a temperature 25° F (14° C) above temperature specifiedon thermostat valve must be completely open at this temperature.

f. Replace a thermostat that fails to meet all of the preceding tests.


90-861329--1 MARCH 1999 Page 6A-7

Installation

1. Clean gasket surfaces on thermostat cover and thermostat housing.

2. Place thermostat in thermostat housing with thermostatic element end toward housing.Be sure to position thermostat so that mounting flange fits into recess in thermostathousing.

3. Coat both sides of new thermostat housing gasket with Quicksilver Perfect Seal andposition on thermostat cover and torque bolts to 30 lb-ft (41 Nm).

73572

ab

140° Thermostat Housing Showna - Thermostat Coverb - Attaching Bolts

4. Reconnect hose to thermostat cover.

5. Start engine and inspect for leaks.

Cold Weather Or Extended Storage

Precautions

WARNINGBE CAREFUL while working on fuel system; gasoline is extremely flammable andhighly explosive under certain conditions. Be sure that ignition key is OFF and donot smoke or allow sources of spark and/or open flames in the area.

WARNINGTo prevent a potential fire hazard, be sure that engine compartment is wellventilated and that there are no gasoline vapors present during starting or foggingof engine.

CAUTIONDO NOT operate engine without water flowing through seawater pickup pump, aspump impeller may be damaged and subsequent overheating damage to engine orsterndrive unit may result.


Page 6A-8 90-861329--1 MARCH 1999

CAUTIONSeawater section of cooling system MUST BE COMPLETELY drained for winterstorage, or immediately after cold weather use, if the possibility of freezing temper-atures exists. Failure to comply may result in trapped water causing freeze and/orcorrosion damage to engine.

CAUTIONIf boat is in the water, seacock (water inlet valve), if equipped, must be closed untilengine is to be re-started, to prevent water from flowing back into cooling systemand/or boat. If boat is not fitted with a seacock, water inlet hose must be discon-nected and plugged to prevent water from flowing back into cooling system and/orboat. As a precautionary measure, attach a tag to the ignition switch or steeringwheel of the boat with the warning that the seacock must be opened or the waterinlet hose reconnected prior to starting engine.

IMPORTANT: Observe the following information to ensure complete draining ofcooling system:

• Engine must be as level as possible.

• A wire should be repeatedly inserted into all drain holes to ensure there are noobstructions in passages. Remove petcock, if necessary, to insert wire complete-ly into drain hole.

IMPORTANT: To prevent threads in manifolds, elbows and cylinder blocks fromrusting out during storage, reinstall plugs using Quicksilver Perfect Seal on threads.Never leave drain plugs out during storage.

NOTE: If possible, place a container under drains and hoses to prevent water from draininginto boat.

CAUTIONCooling system must be completely drained for storage, or trapped water maycause freeze and/or corrosion damage to engine.

Draining InstructionsSINGLE POINT DRAIN SYSTEM

Some models are equipped with a single point drain system consisting of 2 hoses with hard-ware and a T-handle retrieval tool (shown below). This system drains the seawater sectionof the engine only.

76242

a

b



90-861329--1 MARCH 1999 Page 6A-9



76243

a

a - Fittings


76244

a b






Page 6A-10 90-861329--1 MARCH 1999

STANDARD DRAINING PROCEDURES

1. Engine must be level or front of engine slightly higher to properly drain cooling system.

2. Remove drain plugs from cylinder block and manifold.

71424

a



NOTE: It may be necessary to lift, bend, or lower hoses to allow water to drain completelywhen hoses are disconnected.

4. Remove and lower the hoses to allow them to drain.

75815

a

b

140° Thermostat Housing Showna - Inlet Hoseb - Circulating Pump Hose


90-861329--1 MARCH 1999 Page 6A-11


71216

70134

a

b

c

d

e

fc

f

a - Speedometer Pitot Tubeb - Gear Housing Cavity Drain Holec - Trim Tab Cavity Vent Holed - Trim Tab Cavity Drain Passagee - Gear Housing Water Drain Hole (One Each - Port and Starboard)f - Gear Housing Cavity Vent Hole

6. Crank engine over SLIGHTLY, with starter motor, to purge any water trapped inseawater pickup pump. DO NOT ALLOW ENGINE TO START.

7. After seawater section of cooling system has drained completely:

a. Coat threads of drain plugs (except blue plastic plugs with seals) with Perfect Sealand install.

b. Tighten drain plugs securely.

c. Reconnect hoses and tighten all hose clamps securely.

d. If NOT equipped with seacock: Seawater inlet hose must remain disconnectedand plugged until engine is to be restarted.

IMPORTANT: MerCruiser recommends that propylene glycol antifreeze (nontoxicand biodegradable, which makes it friendly to lakes and rivers) be used in seawatersection of the cooling system for cold weather or extended storage. Make sure thatthe propylene glycol antifreeze contains a rust inhibitor and is recommended for usein marine engines. Be certain to follow the propylene glycol manufacturer’s recom-mendations.


Page 6A-12 90-861329--1 MARCH 1999

8. For additional assurance against freezing and rust, remove the thermostat cover andthermostat. Fill the engine seawater cooling system with a mixture of antifreeze and tapwater mixed to manufacturer’s recommendation to protect engine to the lowest temper-ature to which it will be exposed during cold weather or extended storage. Using a newgasket, reinstall thermostat and cover. Tighten cover bolts to 30 lb-ft (41 Nm).

72589

a

c

e

f

g

d

b

76246

b

c

d

c

g

a - Lifting Eyeb - Coverc - Gasketd - Hosee - Thermostatf - Fittingg - Housing

NOTE: Hoses shown removed only to indicate flow. Do not remove hoses.

Recommissioning

NOTICE

Refer to “Cold Weather or Extended Storage Precautions” in this section BEFOREproceeding.




CAUTIONWhen installing battery, be sure to connect NEGATIVE (–) battery cable to NEGA-TIVE (–) battery terminal and POSITIVE (+) battery cable to POSITIVE (+) battery ter-minal. If battery cables are reversed, electrical system damage will result.


90-861329--1 MARCH 1999 Page 6A-13

3. Install fully-charged battery. Clean battery cable clamps and terminals and reconnectcables (see CAUTION listed above). Tighten each cable clamp securely when connect-ing.



6. Perform all checks in the BEFORE STARTING column of the Operation and Mainte-nance Manual OPERATION CHART.



8. Start engine and closely observe instrumentation to make sure that all systems are func-tioning correctly.





Page 6A-14 90-861329--1 MARCH 1999

Auxiliary Hot Water Heater Installation

When connecting a cabin heater or hot water heater to a MerCruiser engine, certain require-ments must be met.

• Supply hose (from engine to heater) and return hose (from heater to engine) MUST NOTEXCEED 5/8 in. (15.8 mm) I.D. (inside diameter).

• Make heater connections ONLY at locations described in the following instructions.

• Check complete system for leaks after heater is connected into cooling system.

• Check for overheating condition (of engine) after heater is connected.

An auxiliary hot water heater kit is not available from Mercury Marine for this modelMerCruiser engine. To connect a cabin heater or hot water heater to these engines, use thefollowing procedure:

1. Drain water from cooling system.

2. Remove plug for thermostat housing at location shown.

50628

a

b

Typicala - Thermostat Housingb - Plug


90-861329--1 MARCH 1999 Page 6A-15

3. Cut hose for return fitting as shown below. Cut approximately 3/4 in. (19 mm) out of hoseto maintain proper hose configuration.

73572

a

Typicala - Cut Hose at This Location

4. Install return fitting in hose and tighten hose clamps securely.

73572

a

Typicala - Return Fitting

5. Connect hot water return hose to return fitting and tighten hose clamps securely.

6. Ensure that hoses do not rub or chafe against any engine components.


Page 6A-16 90-861329--1 MARCH 1999

Cooling System Flow Diagram

MerCruiser engines with standard cooling systems use seawater (water in which the boatis being operated), to remove the heat given off by the engine. The seawater is pumped tothe cooling system by means of an impeller type pickup pump (located in the vertical drive)which picks up seawater, and delivers it to the centrifugal pump (located over an openingon the front of the cylinder block). On some models seawater may be pumped through anoil cooler before going to the circulating pump. The centrifugal pump then circulates the sea-water through the block, head and manifolds, removing heat given off by these parts as itpasses through. After passing through the engine, the seawater is pumped into the exhaustelbow where it mixes with exhaust gases and then is expelled overboard. A thermostaticheat control, which controls circulation of seawater, also is incorporated into the system. Itprovides fast engine warm-up and controlled operating temperature.

50745

q

ji

a

c

h

g

f

e

d

b

kk

l

m

l

m

n n

o p


90-861329--1 MARCH 1999 Page 6A-17

a - Exhaust Elbow Assemblyb - Overboard (Water/Exhaust) Dischargec - Intake And Exhaust Manifold (3.0LX)d - Thermostat Housing And Cover Assemblye - Engine Circulating Pumpf - Engine Block And Head Assembly (181 cid [3.0L])g - Seawater Intake (From Stern Drive)h - Power Steering Cooler, If Equippedi - Coldj - Warmk - To Engine Circulating Pumpl - To Exhaust Manifold

m - Inlet From Stern Driven - Flow From Engine Block And Cylinder Heado - Water Flow Through Thermostat Housing With Thermostat Openp - Water Flow Through Thermostat Housing With Thermostat Closedq - Thermostat Legend


Page 6A-18 90-861329--1 MARCH 1999


6B

CLOSED COOLED MODELSSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 6B-1

COOLING SYSTEMSection 6B - Closed Cooled Models

Table of Contents

Torque Specifications 6B-2. . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 6B-2. . . . . . . . . . Specifications 6B-2. . . . . . . . . . . . . . . . . . . . . . . . . Description 6B-2. . . . . . . . . . . . . . . . . . . . . . . . . . .

Coolant Recovery Bottle 6B-3. . . . . . . . . . . . . Pressure Cap Maintenance 6B-4. . . . . . . . . . . . . Heat Exchanger Repair 6B-5. . . . . . . . . . . . . . . . Testing Closed Cooling System 6B-5. . . . . . . . .

Testing Coolant for Alkalinity 6B-5. . . . . . . . . Pressure Testing System 6B-5. . . . . . . . . . . . Testing for Cylinder Head Gasket Leak 6B-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Testing Heat Exchanger 6B-7. . . . . . . . . . . . . Testing Pressure Cap 6B-7. . . . . . . . . . . . . . .

Thermostat 6B-9. . . . . . . . . . . . . . . . . . . . . . . . . . . Removal 6B-9. . . . . . . . . . . . . . . . . . . . . . . . . . Testing 6B-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation 6B-10. . . . . . . . . . . . . . . . . . . . . . . .

Changing Coolant 6B-11. . . . . . . . . . . . . . . . . . . . Closed Cooling Section 6B-11. . . . . . . . . . . . . Coolant Recommendations 6B-11. . . . . . . . . Change Intervals 6B-11. . . . . . . . . . . . . . . . . . Draining Instructions 6B-12. . . . . . . . . . . . . . . Draining Diagram 6B-14. . . . . . . . . . . . . . . . . .

Cleaning System 6B-15. . . . . . . . . . . . . . . . . . . . . Closed Cooling Section 6B-15. . . . . . . . . . . . . Seawater Section 6B-15. . . . . . . . . . . . . . . . . .

Flushing Seawater Section of Closed Cooling System 6B-17. . . . . . . . . . . . . . . . . . . . . Draining Seawater Section of Closed Cooling System 6B-19. . . . . . . . . . . . . . . . . . . . .

Recommissioning 6B-20. . . . . . . . . . . . . . . . . . Filling Closed Cooling Section 6B-21. . . . . . . . .

CLOSED COOLED MODELS SERVICE MANUAL NUMBER 26

Page 6B-2 90-861329--1 MARCH 1999


Description lb-in. lb-ft Nm

Drain Plugs Securely

Heat Exchanger End Caps 190 22

Reservoir to Thermostat Housing 30 41

Thermostat Cover 20 27

Hose Clamps

Heat Exchanger Mounting BracketsSecurely



Quicksilver 2-4-C Marine Lubricant WithTeflon

92-825407A3


Specifications

Cooling System Capacity 9 (8.5)

Thermostat 143° F (62° C)

Cap Pressure 14 psi (97 kPa)

Description

There are several configurations of this cooling system, but the operation is essentially iden-tical. Basically, the system is composed of two separate subsystems: the seawater systemand the closed cooling system. The seawater system is similar in function to the fan usedin an automobile because it absorbs heat (from the closed cooling system) as it passesthrough the heat exchanger. The closed cooling system is similar in function to the rest ofthe cooling system in an automobile.

The coolant recovery system keeps the reservoir full. Normal coolant overflow into recoverybottle is approximately 1/2 pint (230 ml) during warm-up. The coolant recovery systemdraws coolant back into the reservoir from the recovery bottle as the engine cools. As longas there is coolant in the recovery bottle, the reservoir should remain completely full. If not,there’s a vacuum leak, usually at the hose leaving the reservoir, or the gasket under therecovery filler cap. The gasket seals against the outer rim of the filler neck.

IMPORTANT: The coolant (antifreeze) flows around the outside of the cooling tubeswhile seawater flows through the inside of the cooling tubes in the heat exchanger.

Engine exhaust manifold is seawater cooled. Sterndrive seawater pickup pumps seawaterthrough the heat exchanger.


90-861329--1 MARCH 1999 Page 6B-3

Coolant Recovery BottleBefore starting engine each day, ensure that coolant is visible in coolant recovery bottle.

If coolant is not visible, check fresh water section of cooling system (including coolant recov-ery system) for leaks and repair, as necessary. Refill fresh water section with recommendedcoolant solution, as outlined under “Changing Coolant,” following.

If coolant is visible, start engine and run until it reaches normal operating temperature, thenrecheck coolant level in coolant recovery bottle. Coolant level MUST BE between the ADDand FULL marks (on front of bottle).

WARNINGAllow engine to cool before removing pressure cap, as sudden loss of pressurecould cause hot coolant to boil and discharge violently. After engine has cooled,turn cap 1/4 turn to allow any pressure to escape slowly, then push down and turncap all the way off.

If level is low, remove fill cap from coolant recovery bottle and add required amount of cool-ant solution. Use a 50/50 mixture of ethylene glycol antifreeze and pure, soft water for cool-ant additions. If frequent additions of coolant are required, check fresh water section forleaks.

IMPORTANT: ALCOHOL OR METHANOL BASE ANTIFREEZE OR PLAIN WATER ARENOT RECOMMENDED FOR USE IN COOLING SYSTEM AT ANY TIME. In areas whereethylene glycol is not available, and the possibility of freezing does not exist, it ispermissible to use a solution of rust inhibitor and pure, soft water (mixed tomanufacturer’s recommendations).

Occasionally, ensure that coolant recovery system is functioning properly by removingpressure cap from heat exchanger and checking level. Coolant level should be up to bottomof heat exchanger filler neck. If low, examine entire fresh water section (especially coolantrecovery system) for leaks and repair, if necessary.

IMPORTANT: When reinstalling pressure cap, be sure to tighten it until it contactsstops on filler neck.


Page 6B-4 90-861329--1 MARCH 1999

Pressure Cap MaintenancePressure cap is designed to maintain pressure in fresh water section of closed coolingsystem once the engine has attained normal operating temperature. This raises the boilingpoint of the coolant, thereby increasing the efficiency of the cooling system. To help ensureproper operation, cap should be cleaned, inspected and pressure tested periodically asfollows:

WARNINGAllow engine to cool before removing pressure cap (in next step), as sudden lossof pressure could cause hot coolant to boil and discharge violently. After enginehas cooled, turn cap 1/4 turn to allow any pressure to escape slowly, then pushdown and turn cap all the way off.

1. Remove pressure cap from heat exchanger.

2. Wash cap with clean water to remove any deposits or debris from sealing surfaces.

3. Inspect rubber seal on cap for cuts, cracks or other signs of deterioration. If seal is dam-aged, cap MUST BE replaced.

4. Inspect coolant recovery gasket for deterioration and replace if bad.

5. Check condition of locking tabs on cap. Replace cap if tabs are bent or cracked.

72714

a

bc

a - Rubber Seal (Cap MUST BE Replaced if Damaged)b - Gasket (Look for Cracks under Gasket)c - Locking Tabs (1 Hidden)

6. Refer to “Testing Pressure Cap” and test pressure cap as outlined.

7. Clean sealing surfaces on heat exchanger filler neck with a cloth. Inspect surfaces forany damage or deposits that may prevent cap from sealing properly.

8. Clean coolant recovery passage in heat exchanger filler neck with a wire and blow outwith compressed air.

72715

a

b

a - Inspect for Damageb - Clean Coolant Recovery Passages

9. Reinstall pressure cap, being sure to tighten until it contacts stops on filler neck.


90-861329--1 MARCH 1999 Page 6B-5

Heat Exchanger RepairIMPORTANT: Braze with BCUP 2 rod or silver solder. Care must be taken not to meltother joints during repair.

1. Internal leaks can be repaired by brazing shut the ends of the leaking tube. This is onlya temporary fix because usually another tube will start leaking after a short period of timeand this also causes a reduction in cooling capacity. Do not close more than three tubes.

2. Nipples and drains that have been broken off the heat exchanger can be reattached bybrazing.

Testing Closed Cooling SystemTesting Coolant for Alkalinity

WARNINGAllow engine to cool before removing pressure cap as sudden loss of pressurecould cause hot coolant to boil and discharge violently. After engine has cooled,turn cap 1/4 turn to allow any pressure to escape slowly, then push down and turncap all the way off.

Coolant in fresh water section should be changed every two years and should be checkedfor alkalinity at least once between change intervals. To check coolant for alkalinity, proceedas follows:

1. Obtain pink litmus paper from a local supplier (drug store, pet shop, etc.).

2. Remove pressure cap from heat exchanger and insert one end of litmus paper into cool-ant.

3. If pink litmus paper turns blue, coolant is alkaline and need not be replaced.

4. If pink litmus paper remains pink, coolant is not alkaline and MUST BE REPLACED,as explained under “Changing Coolant.”

Pressure Testing System

WARNINGAllow engine to cool before removing pressure cap. Sudden loss of pressure couldcause hot coolant to boil and discharge violently. After engine has cooled, turn cap1/4 turn to allow any pressure to escape slowly, then push down and turn cap all theway off.

If coolant section of closed cooling system is suspected of leaking or not holding sufficientpressure, and no visible signs of leakage can be found, perform the following test:

1. Remove pressure cap from heat exchanger or reservoir.

2. Clean, inspect and pressure test pressure cap, as outlined under “Testing PressureCap,” to eliminate the possibility that cap is not maintaining proper pressure in systemand is causing coolant to boil over.

3. Clean inside of filler neck to remove any deposits or debris. Examine lower inside seal-ing surface for nicks or other damage. Surface must be perfectly smooth to achieve agood seal between it and rubber seal on cap. Also check locking cams on sides of fillerneck to be sure that they are not bent or damaged. If locking cams are bent or damaged,pressure cap will not hold the proper pressure.

4. Adjust coolant level in fresh water section to 1 in. (25 mm) below filler neck.


Page 6B-6 90-861329--1 MARCH 1999

5. Attach an automotive-type cooling system pressure tester to filler neck and pressurizeclosed cooling section to amount specified in following chart, based on pressure cap rat-ing for your engine.

Pressure Cap RatingAmount of PressureApplied to ClosedCooling System

14 psi (97 kPa) 17 psi (117 kPa)

6. Observe gauge reading for approximately two minutes; pressure should not drop duringthis time. If pressure drops, proceed with the following steps until leakage is found.

7. While maintaining specified pressure on closed cooling section, visually inspect exter-nal portion of cooling system (hoses, gaskets, drain plugs, petcocks, core plugs, circu-lating pump seal, etc.) for leakage. Also listen closely for bubbling or hissing, as theyusually are a sure indication of a leak.

8. Refer to “Testing Heat Exchanger” in this section and test as outlined.

9. If no leakage could be found in above steps, engine is leaking internally, and it probablyis due to one or more of the following: (1) loose cylinder head bolts or damaged gasket,(2) loose intake manifold bolts or damaged gasket, (3) loose exhaust elbow or distribu-tion block retaining nuts or damaged gasket, (4) cracked or porous cylinder head orblock, or (5) cracked or porous exhaust manifold. Proceed as follows until location ofinternal leak is found.

a. Start engine. Re-pressurize system to previously specified amount and observepressure gauge on tester. If needle in gauge vibrates, compression or combustionis leaking into closed cooling section from a leak in the combustion chamber. Exactcylinders, where leakage is taking place, sometimes can be found by removingspark plug wires (one at a time) while observing pressure gauge. Vibration willdecrease or stop when plug wire is removed from leaking cylinder. Stop engine.

b. Remove spark plugs (one at a time) from cylinders and examine for presence ofcoolant. A spark plug that is perfectly clean or milky appearing is a sure indicationof a leak.

c. Drain oil from engine and examine for presence of coolant. Oil usually will be milkyif coolant is present. If coolant is present, remove engine from boat and drop the oilpan. With engine in the upright position, re-pressurize closed cooling section to pre-viously specified amount and examine internal surfaces of engine to locate leak.

d. If no leakage can be found in above steps, entire engine must be disassembled andinspected for leakage.

Testing for Cylinder Head Gasket LeakA leaking head gasket will cause combustion gas to be forced into the cooling system. Themixture of coolant and tiny air bubbles is a poor heat conductor and will overheat an enginequickly. Compression tests or cooling system pressure check normally will not detect theleak because the test pressure is far below the combustion pressures which cause the leak.An effective test is as follows:

IMPORTANT: Run boat in lake for this test. It is best to run the engine at or abovecruising speed during this test. Usually a failed head gasket will not cause the engineto overheat below cruising speed.

1. Install a clear plastic hose between the reservoir and coolant recovery bottle. Use a 2-3ft (61-91 cm) long hose for this test.

2. Route this hose so a “U” is formed.


90-861329--1 MARCH 1999 Page 6B-7

3. Put enough coolant into hose to fill the center 4 or 5 inches (10-13 cm) of the “U.”

4. Observe the “U” while the engine is running.

a. During Idle and Warm-Up: Some coolant and/or air will leave the reservoir.

b. During Cruising Speed (2500-3500 rpm): Coolant and/or air leaving the reservoirshould stop after approximately five minutes running at a given rpm. A leaking headgasket will produce air bubbling through the “U,” going to the coolant recovery bottle.The frequency and size of the bubbles will depend on the size of the leak.

c. At Higher Speeds (4000+ rpm): Normal operation is the same as described in “b”above. A failed head gasket will cause the bubbles to come faster and may beaccompanied by violent, intermittent bursts of coolant.

It is important not to confuse normal warm-up expansion with a failed head gasket. Normalwarm-up produces an intermittent flow of coolant which will stop within approximately fiveminutes at a given rpm. A head gasket leak will not stop because the one thing that marksa failed head gasket is the continued passage of air. This may be accompanied by violent,intermittent bursts of coolant leaving the reservoir. If coolant continues to flow (not in violent,intermittent bursts) from the reservoir at cruising speed, something else besides the headgasket is causing the engine to overheat.

Testing Heat ExchangerFOR INTERNAL LEAK: An internal leak will cause coolant to go into the seawater circuitwhen pressure is put on the closed cooling circuit.

1. Remove a seawater hose from the exchanger. Do not drain the exchanger.

2. Pressurize the closed cooling circuit to 14-20 psi (97-138 kPa) with a radiator tester.

3. If seawater begins to flow from the nipple there is a leak.

FOR BLOCKAGE:

IMPORTANT: Seawater flows THROUGH the tubes in the exchanger. Closed coolingcoolant flows AROUND the tubes.

1. Remove end caps and inspect for any blockage in the seawater circuit (broken impellerblades, weeds, etc.).

2. Remove closed cooling circuit hoses and inspect the tubes just inside the nipples.Because the complete exchanger cannot be inspected, the heat exchanger should bereplaced if blockage is suspected.

Testing Pressure CapPressure cap is designed to maintain a pressure of approximately its rated capacity (referto “Specifications”) in closed cooling section once engine has attained operating tempera-ture. Cap should be cleaned, inspected and pressure-tested at regular tune-up intervals orwhenever cap is suspected of maintaining improper pressure as follows:


1. Carefully remove pressure cap from reservoir or heat exchanger.

2. Wash cap with clean water to remove any deposits or debris from sealing surfaces.


Page 6B-8 90-861329--1 MARCH 1999

3. Inspect gasket (if used) and rubber seal on cap for tears, cuts, cracks or other signs ofdeterioration. Replace gasket, if damaged, or entire cap if rubber seal is damaged.

72714

ac

b

a - Rubber Seal (Cap MUST BE Replaced if Damaged)b - Gasket (Look for Cracks under Gasket)c - Locking Tabs (1 Hidden)

4. Check that locking tabs on cap are not bent or damaged.

5. Using a cooling system pressure tester (similar to one shown), test cap to be sure thatit releases at proper pressure and does not leak. (Refer to instructions which accompa-ny tester for correct test procedure.) Cap must relieve pressure at 14 psi (97 kPa), andmust hold rated pressure for 30 seconds without going below 11 psi. Replace cap if itfails to fall within these limits.

72716

IMPORTANT: Before reinstalling cap in next step, examine lower inside sealing sur-face in filler neck to ensure that it is perfectly smooth and free of debris. Also, inspectcam lock flanges on sides of filler neck to be sure that they are not bent.

6. Examine sealing surface and cam lock flanges as described in important above.

72715

a

b

a - Inspect for Damageb - Cam Lock Flange

7. Reinstall cap on reservoir or heat exchanger.


90-861329--1 MARCH 1999 Page 6B-9

ThermostatRemoval

1. Drain coolant from cylinder block and exhaust manifold.

2. Disconnect hoses from thermostat cover attaching bolts and lock-washers, then removecover and gasket.

3. Remove thermostat from thermostat housing.

73575

a

b

c

a - Boltsb - Reservoirc - Thermostat Housing

Testing1. Clean thermostat in soap and water to remove any deposits or debris.

2. Inspect thermostat for corrosion or other visible damage.

3. If thermostat is suspected of producing insufficient engine temperature, checkthermostat for leakage by holding it up to lighted background. Light leakage around thethermostat valve indicates that thermostat is not closing completely and should bereplaced. (A small amount of leakage at one or two points around the valve perimeteris acceptable.)

72717

a

Brass Thermostat (Stainless Steel Similar)a - Check for Light Leakage Around Perimeter of Valve


Page 6B-10 90-861329--1 MARCH 1999

4. Check opening and closing temperature of thermostat (using a tester similar to the oneshown), as follows:

a. Fill tester to within 1 in. (25 mm) of top with tap water. Do not use distilled water.

b. Open thermostat valve and insert thread. Position thermostat on nylon string so thatit will be just below water level when suspended, then allow valve to close. Suspendthermostat in water.

72675

ab

c

a - Thermometerb - Nylon Stringc - Thermostat

c. Place thermometer in container and position so that bottom of thermometer is evenwith bottom of thermostat. Do not allow thermometer to touch container.

IMPORTANT: When performing instructions “d” and “e,” water must be agitated thor-oughly to obtain accurate results.

d. Plug in tester and observe temperature at which thermostat opens (thermostatdrops off thread). Thermostat must open at 138-145°F (59-63°C). Thermostat mustbe completely open at 170°F (77°C).

e. Unplug tester and allow water to cool to a temperature 10°F (5°C) below specifiedtemperature on thermostat. Thermostat must be completely closed at this tempera-ture.

f. Replace a thermostat that fails to meet all of the preceding tests.

Installation1. Remove thermostat housing and gaskets. Discard gaskets.

2. Clean gasket surfaces on thermostat cover, thermostat housing and intake manifold.

3. Position lower gasket (with continuity rivets) on intake manifold. Place thermostat hous-ing on gasket.

IMPORTANT: If gasket has continuity rivets, do not coat with Quicksilver Perfect Seal,or audio warning temperature switch may not work properly.

4. Install thermostat as shown, into thermostat housing.

72674


90-861329--1 MARCH 1999 Page 6B-11

CAUTIONAvoid seawater pickup pump impeller damage. DO NOT operate engine withoutcooling water being supplied to seawater pickup pump.

5. With boat in the water and/or cooling water properly supplied to seawater pickup pump,start engine and inspect for leaks.

Changing Coolant

NOTICE

For information and procedures on “Draining The Seawater Cooling System,” and“Cold Weather Or Extended Storage,” refer to SECTION 1B.

Closed Cooling SectionClosed cooling section of closed cooling system should be kept filled year-round with rec-ommended coolant solution. Do not drain closed cooling section for storage, as this will pro-mote rusting of internal surfaces. If engine will be exposed to freezing temperatures, makesure that closed cooling section is filled with an ethylene glycol antifreeze and water solu-tion, mixed to manufacturer’s recommended proportions, to protect engine to lowest tem-perature to which it will be exposed. If necessary, change coolant.

Coolant Recommendations

CAUTIONAlcohol or Methanol base antifreeze or plain water are not recommended for use infresh water section of closed cooling system at any time.

MerCruiser recommends the use of Extended Life 5/100 Ethylene Glycol Antifreeze/Cool-ant mixed 50/50 with purified water. If this is not available, use a 50/50 mixture of ethyleneglycol antifreeze and tap water. In areas where temperatures generally do not go below32° F (0° C), rust inhibitor and tap water is acceptable. Extended Life 5/100 Ethylene Gly-col Antifreeze/Coolant should be changed every 5 years or 1,000 hours whichever occursfirst. Any other coolants should be changed every 2 years or 400 hours, whichever occursfirst.

Change IntervalsDrain and flush coolant from the closed cooling system at least every two years or wheneverexhaust gases have entered the system.

Draining Instructions


IMPORTANT: Engine must be as level as possible to ensure complete draining ofcooling system.

IMPORTANT: Closed cooling section must be kept filled year round with recom-mended coolant. If engine will be exposed to freezing temperatures, make sureclosed cooling section is filled with an ethylene glycol antifreeze and water solutionproperly mixed to protect engine to lowest temperature to which it will be exposed.


Page 6B-12 90-861329--1 MARCH 1999

IMPORTANT: Do not use Propylene Glycol Antifreeze in the closed cooling sectionof the engine.

The following draining instructions apply to all engines equipped with closed cooling. Thelocation of petcocks that require opening and hoses that require removal are representedon the following pages for the individual engines.

IMPORTANT: Observe precautions previously outlined before proceeding.

1. Remove pressure cap from coolant tank.

2. Drain coolant from locations as shown for your model and engine. (Refer to the appropri-ate diagram on the following “Draining Diagrams” page.)

3. After coolant has drained completely, coat threads of drain plugs with Quicksilver Per-fect Seal and install drain plugs and hoses. Tighten clamps and drain plugs securely.

4. Remove coolant recovery bottle from mounting bracket and pour out coolant.

5. Clean system as outlined in “Cleaning System.”

6. Fill system as outlined in “Filling Closed Cooling Section.”

SINGLE POINT DRAIN SYSTEM

Some models are equipped with a single point drain system consisting of 2 hoses with hard-ware and a T-handle retrieval tool (shown below). This system drains the seawater sectionof the engine only.

76242

a

b



90-861329--1 MARCH 1999 Page 6B-13



76243

a

a - Fittings


76244

a b






Page 6B-14 90-861329--1 MARCH 1999

Draining Diagram

73665

b

b

b

ba

a

a - Remove and Lower Hoses To Drainb - Remove Drain Plugs Repeatedly Clean Out Holes Using A Stiff Piece Of Wire,

Until Entire System Is Drained.


90-861329--1 MARCH 1999 Page 6B-15

Cleaning System

Closed Cooling SectionClosed cooling section of the cooling system should be cleaned at least once every twoyears or whenever decreased cooling efficiency is experienced.

A good grade automotive cooling system cleaning solution may be used to remove rust,scale or other foreign material. Always follow manufacturer’s instructions for the cleaner.

If closed cooling section is extremely dirty, a pressure flushing device may be used to flushout remaining deposits. Flushing should be done in direction opposite normal coolant flowto allow water to get behind deposits and force them out. Refer to instructions which accom-pany flushing device for proper hookup and flushing procedure.

NOTICE

For information and procedures on “Draining And Flushing The Seawater CoolingSystem,” and “Cold Weather Or Extended Storage,” refer to SECTION 1B.

Seawater SectionCooling efficiency of an engine with closed cooling is greatly dependent upon heat transferthrough the tubes within the heat exchanger. During engine operation, contaminants withinthe seawater (such as salt, silt, lime, etc.) collect on the inside of the tubes, thus reducingheat transfer and greatly decreasing heat exchanger efficiency. It is, therefore, recom-mended that the seawater section of the heat exchanger be cleaned at least once every twoyears or whenever decreased cooling efficiency is suspected, as follows:

IMPORTANT: It may be necessary to remove heat exchanger on some models. If heatexchanger is removed, be sure to refill closed cooling section with coolant.

1. Remove seawater drain plug from bottom of heat exchanger and allow water to drain.After water has drained completely, coat threads of drain plug with Quicksilver PerfectSeal and reinstall.


Page 6B-16 90-861329--1 MARCH 1999

2. Remove bolts which secure end plate to each end of heat exchanger, then remove endplates, seal washers and gaskets. Discard seal washers and gaskets. Clean gasketmaterial from end plate and heat exchanger.

73581

71515

a

b

cd

e

b

a - Boltb - End Capc - Sealing Washerd - Gaskete - Drain Plug

3. Clean water passages in heat exchanger by inserting a suitable size wire brush intoeach passage. Use compressed air to blow loose particles out of water passages.

4. Apply Quicksilver Perfect Seal to both sides of new end plate gaskets, then reinstall endplates, using new gaskets and seal washers. (Be sure to install seal washers betweenend plates and gaskets.) Torque end plate bolts to specifications.

CAUTIONAvoid seawater pickup pump impeller damage. DO NOT operate engine withoutwater being supplied to seawater pickup pump.

5. With boat in the water and/or cooling water properly supplied to seawater pickup pump,start engine and inspect for leaks.


90-861329--1 MARCH 1999 Page 6B-17

Flushing Seawater Section of Closed Cooling System

If engine is operated in salty, polluted or mineral-laden waters, seawater section of closedcooling system should be flushed periodically (preferably after each use) with fresh waterto reduce corrosion and prevent the accumulation of deposits in the system. Seawater sec-tion also should be thoroughly flushed prior to storage.

WARNINGWhen flushing cooling system with boat out of the water, be certain that area invicinity of propeller is clear and that no person is standing nearby. As aprecautionary measure, it is recommended that propeller be removed.


CAUTIONIf cooling system is to be flushed with boat in the water, seacock (if so equipped)must be closed, or water inlet hose must be disconnected and plugged to preventwater from flowing into boat.

CAUTIONTo prevent engine or sterndrive unit damage DO NOT run engine or drive unit with-out water being supplied to water intake openings on gear housing.

CAUTIONWatch temperature gauge at dash to ensure the engine does not overheat.

1. Connect flushing attachment as follows:

NOTE: If flushing cooling system with boat in water, raise drive unit to trailer position, installflushing attachment and lower drive unit to full IN/DOWN position.

a. Install Quicksilver Flushing Attachment (or equivalent) over water intake openingsin gear housing.

b. Connect hose between flushing attachment and water tap.

72672

a

b

a - Quicksilver Flushing Attachmentb - Water Hose


Page 6B-18 90-861329--1 MARCH 1999

CAUTIONIf cooling system is to be flushed with boat in the water, seacock (if so equipped)must be closed, or water inlet hose must be disconnected and plugged to preventwater from flowing into boat.

c. Close seacock (if so equipped) or disconnect and plug seawater inlet hose.

2. Partially open water tap (approximately 1/2 maximum capacity) and allow drive unit andcooling system to fill completely. Do not use full tap water pressure.

NOTE: Drive unit is full when water is discharged out of drive unit, and/or seawater sectionof closed cooled system is full when water is discharged through propeller.

3. Place remote control lever in NEUTRAL position and start the engine. Operate engineat idle speed in NEUTRAL gear for 10 minutes or until discharge water is clear, then stopengine.

4. Shut off tap water. Remove hose and flushing attachment from drive unit. On belt drivenseawater pickup pump models, also remove hose and flushing attachment from pumpinlet.

5. Follow instructions “a” or “b.”

CAUTIONIf boat is in the water or is to remain in the water, seacock (if so equipped) must re-main closed until engine is to be restarted, to prevent contaminated water fromflowing back into cooling system. If boat is not fitted with a seacock, water inlethose must be left disconnected and plugged, to prevent contaminated water fromflowing into cooling system and/or boat. As a precautionary measure, attach a tagto the ignition switch or steering wheel with the warning that the seacock must beopened or the water inlet hose reconnected prior to starting the engine.

a. If equipped with seacock: Observing precaution above, open seacock.

b. If NOT equipped with seacock: Observing precaution above, remove plug fromseawater inlet hose and reconnect seawater inlet hose. Tighten hose clampssecurely.


90-861329--1 MARCH 1999 Page 6B-19

Draining Seawater Section of Closed Cooling System

NOTICE

For “Cold Weather Or Extended Storage” information and procedures, refer toSECTION 1B.


CAUTIONIf boat is in the water or is to remain in the water, seacock (if so equipped) mustremain closed until engine is to be restarted, to prevent contaminated water fromflowing back into cooling system. If boat is not fitted with a seacock, water inlethose must be left disconnected and plugged, to prevent contaminated water fromflowing into cooling system and/or boat. As a precautionary measure, attach a tagto the ignition switch or steering wheel with the warning that the seacock must beopened or the water inlet hose reconnected prior to starting the engine.

1. Close seacock (if so equipped) or disconnect and plug seawater inlet hose.

2. Check that engine is as level as possible to ensure complete draining of cooling system.

3. Remove drain plugs from exhaust manifold.

71424

a


4. Remove aft (rear) drain plug from heat exchanger.

71423

a

a - Drain Plug




Page 6B-20 90-861329--1 MARCH 1999

6. After seawater section of cooling system has been drained completely, coat threads ofdrain plugs with Quicksilver Perfect Seal and reinstall. Tighten drain plugs securely.Reconnect hoses and tighten all hose clamps securely. If NOT equipped withseacock: seawater inlet hose must remain disconnected and plugged until engine is tobe restarted.


71216

70134

a

b

c

d

e

f

fc

a - Speedometer Pitot Tubeb - Trim Tab Cavity Vent Holec - Trim Tab Cavity Drain Passaged - Gear Housing Water Drain Hole (One Each - Port and Starboard)e - Gear Housing Cavity Vent Holef - Gear Housing Cavity Drain Hole

8. Crank engine over SLIGHTLY with starter motor to purge any water trapped in seawaterpickup pump. DO NOT ALLOW ENGINE TO START.

Recommissioning

NOTICE

Refer to “Cold Weather or Extended Storage Precautions,” in this sectionBEFORE proceeding.




CAUTIONWhen installing battery, be sure to connect NEGATIVE (–) battery cable to NEGA-TIVE (–) battery terminal and POSITIVE (+) battery cable to POSITIVE (+) battery ter-minal. If battery cables are reversed, electrical system damage will result.

3. Install fully-charged battery. Clean battery cable clamps and terminals and reconnectcables (see CAUTION listed above). Tighten each cable clamp securely when con-necting.



90-861329--1 MARCH 1999 Page 6B-21


6. Perform all checks in the BEFORE STARTING column of the Operation and Mainte-nance Manual OPERATION CHART.



8. Start engine and closely observe instrumentation to make sure that all systems are func-tioning correctly.




Filling Closed Cooling Section

NOTICE

See “Specifications” for approximate closed cooling system capacity and coolantrecommendations

WARNINGDo not remove coolant cap when engine is hot. Coolant may discharge violently.

CAUTIONAlcohol or Methanol based antifreeze or plain water are not recommended for usein fresh water section of cooling system at any time.

CAUTIONFront of engine should be higher than rear to purge trapped air out of the systemduring initial filling. This will minimize the possibility of air being trapped in theclosed cooling section which can cause engine to overheat.

1. Remove coolant cap on heat exchanger.

2. Fill closed cooling system with coolant mixture through heat exchanger fill neck untilcoolant level is 1 in. (25 mm) below filler neck.

CAUTIONAvoid seawater pickup pump impeller damage and subsequent overheating dam-age to sterndrive unit. DO NOT operate engine without water being supplied to sea-water pickup pump.

CAUTIONModels with belt drive seawater pickup pump must be in the water when runningengine because garden hose will not supply enough water to system at higher rpm.

3. With pressure cap off, start engine and run at fast idle (1500-1800 rpm). Add coolantsolution to heat exchanger, as required, to maintain coolant level 1 in. (25 mm) belowfiller neck.


Page 6B-22 90-861329--1 MARCH 1999

4. After engine has reached normal operating temperature (thermostat is fully open), andcoolant level remains constant, fill heat exchanger to bottom of filler neck.

5. Observe engine temperature gauge to make sure that engine operating temperature isnormal. If gauge indicates excessive temperature, stop engine immediately andexamine for cause.

6. Install pressure cap on heat exchanger.

7. Remove cap from coolant recovery reservoir and fill to FULL mark with coolant solution.Reinstall cap.

8. With engine still running, check hose connection, fittings and gaskets for leaks.

IMPORTANT: Engine overheating is often due to air being trapped in closed coolingsection. Purge air by running engine at 2000 rpm for 10 minutes.


9. Recheck coolant level after first open-throttle boat test and add coolant, if necessary.

10. Maintain coolant level in coolant recovery reservoir between ADD and FULL marks withengine at normal operating temperature.

7A

MANIFOLDSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 7A-1

EXHAUST SYSTEMSection 7A - Manifold

Table of Contents

Torque Specifications 7A-2. . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 7A-2. . . . . . . . . . Exhaust System 7A-2. . . . . . . . . . . . . . . . . . . . . . .

Through Drive Unit Exhaust 7A-2. . . . . . . . . . Removal 7A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cleaning and Inspection 7A-3. . . . . . . . . . . . . . . .

Installation 7A-4. . . . . . . . . . . . . . . . . . . . . . . . . . . Upper Exhaust Pipe and Shutter Replacement 7A-5. . . . . . . . . . . . . . . . . . . . . . . . Lower Exhaust Pipe Replacement 7A-6. . . . . . . Emissions Testing 7A-7. . . . . . . . . . . . . . . . . . . . .

Installing Test Probes 7A-7. . . . . . . . . . . . . . .

MANIFOLD SERVICE MANUAL NUMBER 26

Page 7A-2 90-861329--1 MARCH 1999



Hose Clamps Securely

Exhaust Elbow 20-25 27-34

Exhaust Pipe to Gimbal Housing 20-25 27-34



Quicksilver Loctite 27131 92-809820


Exhaust System

Through Drive Unit Exhaust

CAUTIONIt is the responsibility of the boat manufacturer or installing dealer to properlylocate the engine and install the exhaust system. Improper installation may allowwater to enter the exhaust manifolds and combustion chambers and severelydamage the engine. Damage caused by water in the engine will not be covered byMerCruiser Warranty, unless this damage is the result of defective part(s).

MEASURING FOR RISERS

Gasoline Engines

Determine if exhaust elbow risers are required by taking measurements (a) and (b) with boatat rest in the water and maximum load aboard. Subtract (b) from (a) to find (c). If (c) is lessthan specified in chart, select appropriate size exhaust elbow riser kit and exhaust extensionkit that will correctly position exhaust elbow.

Model (c) = (a) Minus (b)

3.0L (c) Must Be 11 in. (279 mm) or More

22471

d

ab c

MCM 3.0L Engine


90-861329--1 MARCH 1999 Page 7A-3

Removal1. Disconnect battery cables from battery.

2. Drain water from cylinder block, exhaust manifold and exhaust elbow.

3. Disconnect throttle cable at carburetor.

4. Disconnect exhaust hose and cooling hoses.

5. Disconnect fuel line at carburetor.

WARNINGGasoline is extremely flammable and highly explosive under certain conditions. Besure electrical source to engine is disconnected. Do not smoke or allow sources ofspark or open flame in area when installing new pump. Wipe up any spilled fuelimmediately.

6. Disconnect crankcase ventilation hose at rocker arm cover.

7. Disconnect wires connected to electric choke.

8. Remove exhaust manifold fasteners; remove manifold assembly and discard gaskets.

9. Remove exhaust elbow.

Cleaning and Inspection1. Clean gasket material from all surfaces and wash parts in solvent.

2. Inspect all parts carefully. Machined surfaces must be clean and free of all marks anddeep scratches, or water and exhaust leaks may result.

3. Check water passages for foreign material. Passages must be clean for efficient cooling.

4. If more thorough inspection is desired, pipe plugs may be removed from exhaustmanifold and exhaust elbow.

IMPORTANT: If plugs are removed, coat threads with Perfect Seal before reinstalling.

IMPORTANT: If manifold to cylinder head studs have broken, install all new studs withLoctite 27131 AFTER checking head and manifold surfaces for warpage. Also use allnew manifold attaching nuts.

5. Check for cracks.

6. To test manifold body for leaks, block off plates, plugs or short hoses with plugged endsmust be used. One block off plate must have a threaded hole for attaching compressedair hose. Use new gaskets when installing block off plate(s). Apply 40 psi (276 kPa) ofair pressure and submerge manifold in water. Air bubbles will indicate a leak.


Page 7A-4 90-861329--1 MARCH 1999

Installation

If exhaust manifold body requires replacement, transfer all parts (from old manifold) to newmanifold body.

1. Position new gasket on head and install manifold in position, making sure gasket is inplace.

2. Tighten fasteners evenly and torque to 23 lb-ft (33 Nm), starting in center and workingout toward ends.

IMPORTANT: After engine has been brought up to operating temperature, allowengine to cool. Retorque manifold fasteners.

3. Install carburetor (if removed) and connect crankcase ventilation hose at rocker armcover.

4. Install exhaust elbow using new gasket. Torque to 25 lb-ft (34 Nm).

5. Install gasket as shown:

50677

a

a - Gasket (not shown)

6. Connect throttle cable to carburetor. Adjust as outlined in “Removal, Installation andAlignment.”

7. Connect fuel line and electric choke wires.

8. Reinstall exhaust and cooling hoses.

9. Reconnect battery cables to battery. Tighten securely.

10. Start engine, check for exhaust, water and fuel leaks and adjust carburetor idle speedand mixture.


90-861329--1 MARCH 1999 Page 7A-5

Upper Exhaust Pipe and Shutter ReplacementIMPORTANT: Engine does not have to be removed, however, exhaust elbow may haveto be removed.

1. Loosen exhaust bellows clamps.

2. Remove hose clamps.

3. Remove intermediate exhaust pipe.

4. Remove exhaust tube.

75819

a

c

b

a

a - Clampsb - Lower Exhaust Tubec - Intermediate Exhaust Pipe

5. Replace shutter (in lower pipe), as shown.

a. Slide hose on lower pipe. Tighten clamps securely.

b. Place clamps over bellows and connector hose, then install upper exhaust pipe.

c. Making sure all clamps are contacting exhaust elbow, upper pipe and lower pipe,tighten clamps securely.

74552

a

cd

b

a - Connector Hose - Remove to Change Shutterb - Clamps (2)c - Grommet (2)d - Shutter - Opens Downward


Page 7A-6 90-861329--1 MARCH 1999

Lower Exhaust Pipe Replacement

1. Remove sterndrive unit.

2. Remove engine, then upper exhaust pipe.

3. Remove screws and lockwashers that secure lower exhaust pipe to gimbal housing.

50634

a

b

a - Exhaust Pipeb - Screws (4) - 2 Under Exhaust Pipe

4. Remove exhaust pipe and O-ring.

5. Clean mating surfaces on pipe and gimbal housing.

6. Place O-ring in groove of gimbal housing.

72736

a

b

a - Mating Surfacesb - O-ring

7. Reinstall lower exhaust pipe with screws and lock-washers, torque to specifications. Becertain that O-ring remains seated in groove, properly sealing joint to prevent leakage.

8. Reinstall upper exhaust pipe, then engine.

9. Reinstall sterndrive unit.


90-861329--1 MARCH 1999 Page 7A-7

Emissions Testing

Installing Test ProbesIMPORTANT: The testing dealer or agency will be equipped with the appropriate testequipment and adapters for this engine. The test probes should be installed as fol-lows:

1. Remove plug from exhaust elbow.

74645

2. Install exhaust elbow adapter fitting into elbow. Apply Loctite Pipe Sealant with Teflonto threads that go into elbow. Tighten it securely.

3. Insert exhaust probe into fitting and tighten securely.

71926

74644

The testing agency will connect their adapter and test equipment to the probe to conductthe test. Once the test is complete, remove the test probe and fitting. Apply Quicksilver Per-fect Seal to the threads of plug and reinstall into elbow.


Page 7A-8 90-861329--1 MARCH 1999


8A

POWER STEERING PUMPSERVICE MANUAL NUMBER 26

90-861329--1 MARCH 1999 Page 8A-1

POWER STEERINGSection 8A - Power Steering Pump

Table of Contents

Torque Specifications 8A-2. . . . . . . . . . . . . . . . . . Tools 8A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Special Tools 8A-2. . . . . . . . . . . . . . . . . . . . . . . Lubricants/Sealants/Adhesives 8A-2. . . . . . . . . . Precautions 8A-2. . . . . . . . . . . . . . . . . . . . . . . . . . Checking Power Steering Pump Fluid Level 8A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

With Cold Engine 8A-3. . . . . . . . . . . . . . . . . . . With Warm Engine 8A-4. . . . . . . . . . . . . . . . . .

Filling and Air Bleeding Power Steering System 8A-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump Drive Belt Tension Adjustment 8A-5. . . . .

Pump Pulley Replacement 8A-6. . . . . . . . . . . Power Steering Pump And Cooler 8A-7. . . . . . .

Replacement 8A-7. . . . . . . . . . . . . . . . . . . . . . . Low Pressure Hose (Control Valve-to- Cooler) 8A-12. . . . . . . . . . . . . . . . . . . . . . . . . . System Flow Diagram 8A-14. . . . . . . . . . . . . .

POWER STEERING PUMP SERVICE MANUAL NUMBER 26

Page 8A-2 90-861329--1 MARCH 1999


Fastener Location lb-ft lb-in. Nm

Pump MountingBracket to Engine

30 41

Circulating PumpPulley

240 27

Tools


Pulley Installer 91-93656A1

Special Tools

Kent-Moore Special Tools


Kent-Moore Tools, Inc.29784 Little Mack


Pulley Removal Tool J-25034




Dexron II (ATF) Obtain Locally

Precautions

CAUTIONDo not operate engine without cooling water being supplied to water pickup pumpor water pump impeller will be damaged and subsequent overheating damage toengine may result.

WARNINGAlways disconnect battery cables from battery before working on engine to preventfire or explosion.

CAUTIONDo not pry on power steering pump or alternator when adjusting belt tension.Serious damage may result.


90-861329--1 MARCH 1999 Page 8A-3

Checking Power Steering Pump Fluid Level

IMPORTANT: Use only Quicksilver Power Trim and Steering Fluid, or automatic trans-mission fluid (ATF), Dexron II, in power steering system.

With Cold Engine1. Stop engine and position drive unit so that it is straight back.


75809

a

b

a - Fill Capb - Power Steering Pump

3. Level should be between “FULL COLD” mark and bottom of dipstick.

72519a

a - Proper Fluid Level With Engine Cold

4. If fluid level is low but still visible in pump reservoir, add fluid through fill cap opening tobring level up to “ COLD” mark on dipstick. Do not overfill.


Page 8A-4 90-861329--1 MARCH 1999

With Warm Engine1. Stop engine and position drive unit so that it is straight back.


3. Level should be between the “FULL HOT” mark and “ADD” mark on the dipstick.

72518a

a - Proper Fluid Level With Engine Warm

4. If level is low (below “ADD” mark), but still visible in pump reservoir, add fluid throughfill cap opening to bring level up to “FULL HOT” mark on dipstick. Do not overfill.

Filling and Air Bleeding Power Steering SystemIMPORTANT: Power steering system must be filled exactly as explained, following,to be sure that all air is bled from the system. All air must be removed, or fluid in pumpmay foam during operation and be discharged from pump reservoir. Foamy fluid mayalso cause power steering system to become spongy resulting in poor boat control.

1. Position drive unit so that it is straight back. Remove cap from power steering pump andcheck fluid level with dipstick attached to fill cap (provided). Add fluid as required, tobring level up to correct level.

IMPORTANT: Use only Quicksilver Power Trim and Steering Fluid, or automatic trans-mission fluid (ATF), Dexron II, in power steering system.

2. Turn steering wheel back-and-forth to end of travel in each direction several times: then,recheck fluid level and add fluid, if necessary.

3. Install vented fill cap.

CAUTIONDO NOT operate engine without water being supplied to seawater pump pickup orpump impeller may be damaged and subsequent overheating damage to enginemay result.

4. Start engine and run at fast idle (1000-1500 rpm) until engine reaches normal operatingtemperature. During this time, turn steering wheel back-and-forth to end of travel in eachdirection several times.

5. Position drive unit so that it is straight back and stop engine. Remove fill cap from pump.Allow any foam in pump reservoir to disperse; then, check fluid level and fluid asrequired, to bring level up to “FULL HOT” mark on dipstick. Do not overfill. Install fill capsecurely.

IMPORTANT: Drive unit must be positioned straight back and power steering fluidmust be hot to accurately check fluid level.

6. If fluid is still foamy (in Step 5), repeat Steps 4 and 5 until fluid does not foam and levelremains constant.


90-861329--1 MARCH 1999 Page 8A-5

Pump Drive Belt Tension Adjustment

NOTICE


IMPORTANT: DO NOT pry in pump body.

1. Install drive belt on pulleys and adjust tension as follows:

a. Pivot pump attain tension.

b. Tighten retaining bolts.

2. Check belt tension using either of two methods, following and readjust pump, if neces-sary, to obtain proper belt tension.

a. Using a strand tension gauge, take gauge reading at midpoint of power steeringpump belt. Gauge should read 75-95 lbs. (334-423 Nm).

b. Check belt tension by pushing down on upper strand of belt at belt midpoint. Beltshould depress 1/4 in. (6 mm).

75809

a

a - Measure Belt Deflection Here


Page 8A-6 90-861329--1 MARCH 1999

Pump Pulley Replacement

REMOVAL

IMPORTANT: Kent-Moore Tool J-25034 must be used to remove the pressed-onpulleys used on power steering pumps. This tool has an end on it that will notmushroom the end of the pump shaft. DO NOT use Kent-Moore Tool J-21239 toremove these pulleys. This tool has a tapered end and will damage the shaft.

1. Install Kent-Moore Tool J-25034 on end of pulley and shaft as shown.

2. While holding tool with suitable wrench, turn threaded screw until pulley is removed.

72821

a

a - Kent-Moore Pulley Removal Tool (J-25034)

INSTALLATION

Install pulley, as follows, using pulley installer tool (91-93656A1), and a long straight edge:

1. Place pulley on pump shaft.

2. Thread stud all the way into pump shaft. Place bearing over stud. Do not use spacer fromkit.

3. Thread nut onto shaft. Thread tool shaft (and nut) all the way onto stud (threaded intopump pulley).

4. Using a long straight edge (to check drive belt alignment), turn large pusher nut untildrive belt is parallel to straight edge.


90-861329--1 MARCH 1999 Page 8A-7

Power Steering Pump And Cooler

Replacement

NOTICE

Refer to “Precautions” in this section BEFORE proceeding.

1. Install pulley.

74562

2. Install bolts and torque to 20 lb-ft (27 Nm).

74563

a

a - Bolts and Lockwashers


Page 8A-8 90-861329--1 MARCH 1999

3. Install 40 inch (1016 mm) drive belt.

74564

a

a - 40 inch (1016 mm) Drive Belt

4. Install 37 inch (940 mm) drive belt over circulating pump pulley.

74565

a



90-861329--1 MARCH 1999 Page 8A-9

5. Install front mount assembly with power steering pump assembly. Tighten boltssecurely.

74558

a b

a - 2-3/4 inch (70 mm) Bolts, Washers and Lockwashersb - Bolts, Washers and Lockwashers

6. Attach power steering pump bracket to engine. Torque bolt to 30 lb-ft (41 Nm).

74559

a

a - 1-1/4 inch (32 mm) Long Bolt Without Closed Cooling. 1-1/2 inch (38 mm) LongBolt With Closed Cooling.

7. Attach power steering pump brace to pump.

74560

a - 7/8 inch (22 mm) Long Bolt and Washer


Page 8A-10 90-861329--1 MARCH 1999

8. Install 37 inch (940 mm) drive belt over pump pulley.

74561

a


9. Adjust drive belt tension.

10. Route hydraulic hoses as shown.

11. Install fluid cooler and tighten hose clamp-screw securely.

75812

a

a - Clamp

12. Install long water hose and tighten hose clamps securely.

13. Install water hoses to power steering fluid cooler and tighten clamps securely.

75812

a

a - Clamps


90-861329--1 MARCH 1999 Page 8A-11

INSTALLATION

1. Using hose clamp, install new hose on back of pump. Tighten clamp securely.

72848

a

b

a - Hose Clampb - Hose

2. Using hose clamp, install hose on fluid cooler. Tighten clamp securely.

73579

c

a

b

a - Fluid Coolerb - Hose Clampc - Hose

3. Fill and air bleed system. Refer to Section 1B “Maintenance” (see “Table of Contents”).


Page 8A-12 90-861329--1 MARCH 1999

Low Pressure Hose (Control Valve-to-Cooler)

REMOVAL

NOTE: Catch fluid that drains from hose, cooler and pump in a suitable container.

1. Loosen hose clamp and remove hose from fluid cooler.

73579

c

a

b


2. Remove large fitting from control valve at transom. Remove hose.

73786

a

a - Fitting


90-861329--1 MARCH 1999 Page 8A-13

INSTALLATION

CAUTIONRoute hoses exactly as shown below. This will help avoid stress on the hose fittingsand will help avoid kinks in the hoses.

IMPORTANT: Be careful to not cross-thread or overtighten hose fittings.

1. Thread large fitting into control valve. Position hose properly (as prior to removal).

2. Torque fittings to 23 lb-ft (31 Nm).

73786

3. Route hose along flywheel housing and secure with J-clamp(s) provided.

4. Using hose clamp, install hose on fluid cooler. Tighten clamp securely.

73579

c

a

b


5. Fill and air bleed system. Refer to SECTION 1B “Maintenance” (see “Table of Con-tents”).


Page 8A-14 90-861329--1 MARCH 1999

System Flow Diagram

72995

�

�

�

�

�

�

�

a

b

c

d

e

f

fd

e

c

g

hi

1 - Reservoir Bottle and Bracket2 - Priority Valve and Mounting Bracket3 - Power Steering Control Valve4 - Power Steering Pump5 - Power Steering Fluid Coolera - Pressure Hose (Fitting on Both Ends - Supplied in Kit)b - Return Hose (Fitting on One End - Supplied in Kit)c - Return Hose from Pump (Cut from Bulk Hose Supplied)d - Pressure Hose from Pumpe - Return Hose from Pumpf - Gravity Feed Hose (Cut from Bulk Hose Supplied)g - Pressure Lineh - Return Linei - Gravity Feed Line


90-861329--1 MARCH 1999 Page 8A-15



Page 8A-16 90-861329--1 MARCH 1999


Mercruiser 4 Cyl 3.0 Service Manual

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Transcript of Mercruiser 4 Cyl 3.0 Service Manual